: Torque Management VS Traction Control Reduced Torque



AJxtcman
05-18-07, 11:46 AM
96 to 99 Information

Torque Management
Torque Management is a function of the PCM that reduces engine power under certain conditions. Torque management is performed for three reasons:

• To prevent overstress of powertrain components.

• To limit engine power when brakes are applied.

• To prevent damage to the vehicle during certain abusive maneuvers.

The PCM uses manifold vacuum, intake air temperature, spark retard, engine speed, engine coolant temperature, A/C clutch status, and EGR valve position to calculate engine output torque. It then looks at torque converter status, transaxle gear ratio, and brake switch inputs and determines if any torque reduction is required. If torque reduction is required, the PCM retards spark as appropriate to reduce engine torque output. In the case of abusive maneuvers, the PCM may also shut off fuel to certain cylinders to reduce engine power.

There are five instances when engine power reduction is likely to be experienced

• During transaxle upshifts and downshifts.

• Heavy acceleration from a standing start.

• If brakes are applied with moderate to heavy throttle (input supplied by the Extended Travel Brake switch).

• When the driver is performing stress-inducing (abusive) maneuvers such as shifting into gear at high throttle angles.

In the first two instances, the driver is unlikely to even notice the torque management actions. In the other cases, engine power output will be moderate at full throttle.

When the PCM determines that engine power reduction is required, it calculates the amount of spark retard necessary to reduce power by the desired amount. This spark retard is then subtracted from the current spark advance. In the case of abusive maneuvers, the fuel injectors for cylinders 1, 4, 6, and 7 will also be disabled for a period of time.

Traction Control
Traction Control is a function of the PCM and the EBTCM that reduces front wheel slip during acceleration by applying the front brakes and reducing engine power. Refer to Brakes for an explanation of the EBTCMs role in traction control. The PCM continuously sends out a PWM signal that indicates the torque output of the powertrain. This signal, referred to as the Delivered Torque signal, is used by the EBTCM to determine what action is required when it sees the front wheels slipping. The EBTCM may decide to apply the front brakes only or apply the front brakes and request reduced torque output from the powertrain. The EBTCM requests reduced torque using another PWM signal. This signal, referred to as the Desired Torque signal, is used by the PCM to determine if the EBTCM is requesting reduced torque output from the powertrain. If the EBTCM requests reduced torque, the PCM will disable between one and seven fuel injectors to achieve this.

Desired Torque will normally be a 90 percent duty cycle signal to the PCM. When the EBTCM decides to request reduced engine power, it decreases the duty cycle of the Desired Torque signal by the amount of torque reduction required (90 percent duty cycle means no torque reduction, 10 percent duty cycle means 100% torque reduction). The PCM responds by shutting off fuel to one or more cylinders depending on the percent torque reduction requested. The PCM will not shut off any fuel injectors if any of the following conditions are present

• Coolant temperature is below -40°C (-40°F) or above 131°C (268°F).

• A low coolant level is present.

• Engine speed is below 600 rpm

The disabled fuel injectors will be re-enabled one by one as the need for traction control ends.

Several DTCs disable traction control when set. They will also trigger a TRACTION OFF light or message. The PCM traction control override also disables traction control and triggers the message. To diagnose a Traction Off light/message, diagnose any DTCs set first. Then check the traction control override and, if active, deactivate the override. If the TRACTION OFF light/message is still present, refer to Brakes for further diagnosis.

.
.
PCM
Fuel Shut-Off Mode
The PCM has the ability to completely turn all the injectors Off or selectively turn Off some of the injectors when certain conditions are met. These fuel shut-off modes allow the Northstar powertrain to protect itself from damage and also improve its driveability.

The PCM will disable all eight injectors under the following conditions:

Ignition Off (prevents engine run-on).
Ignition On but no ignition reference signal (prevents flooding or backfiring).
High engine speed (above red line).
High vehicle speed (above rated tire speed).
Extended high speed closed throttle coastdown (reduces emissions and increases engine braking).
The PCM will selectively disable up to four injectors under the following conditions:

Torque Management enabled (transaxle shifts or abusive maneuvers).
Traction Control enabled (in conjunction with front brakes applying).
Low coolant condition (protects engine from overheating).
.
.
.
.
TCS
Traction Control
Traction control will not have any effect on the operation of the vehicle until the control module detects one or both of the front wheels rotating faster than the rear wheels. At this time the electronic brake and traction control module (EBTCM) will request the powertrain control module (PCM) to reduce the amount of torque applied to the drive wheels. The PCM does this by retarding timing and selectively turning off fuel injectors (up to a maximum of 5). The EBTCM will apply the front brakes, thus reducing torque to the front wheels. Once the front wheels begin to rotate at the same speed as the rear wheels, the system will return full control to the driver. During the traction control mode, if the brake is applied to only one front wheel, most of the torque from the engine will be directed to the other front wheel which will improve the traction of the vehicle.

The braking is accomplished by closing the TCS master cylinder isolating valves, this isolates the master cylinder from the rest of the system. The TCS Prime valves open to allow the pump to get brake fluid to build pressure for braking. The drive wheel circuit solenoids are energized as needed to allow for pressure hold, pressure increase, or pressure decrease.

The TCS may be deactivated by the driver if desired. In order to deactivate the TCS with the engine running, depress the traction control switch. The system will remain deactivated until the ignition switch is cycled, or the switch is pressed again.
.
.
.
.
I will supply more info on other years

CadillacSTS42005
05-20-07, 07:17 AM
but
if you turn off a 96-99 tc with the button you lose 1st gear...

AJxtcman
05-20-07, 02:26 PM
The T/C output (Desired Torque signal) sent to the PCM as an input. When the PCM has a value of 100% the input is a 90 to 95% PWM at 128 hertz signal from the ABS/TC pulled low.
If the PCM has a constant 90% PWM signal. The PCM will not reduce Torque in this part of the program. It can reduce torque from the torque management, but it will not be from wheel spin.
If you add a PWM driver that hold the circuit at the 90 to 95%, but can be switched back to the cars system with a flip of a switch. Then you have a good piggy backed system.

msta293412
05-20-07, 07:45 PM
uh......yea...what he said.

CadillacSTS42005
05-20-07, 09:34 PM
or just tap into the brake switch on the pedal and turn it on so it detects you pressing the brake when your not so it shuts t.c down

AJxtcman
05-21-07, 01:07 PM
or just tap into the brake switch on the pedal and turn it on so it detects you pressing the brake when your not so it shuts t.c down

If the brake is applied it will go into PCM Torque Management. read the attached file.

• To limit engine power when brakes are applied.


• If brakes are applied with moderate to heavy throttle (input supplied by the Extended Travel Brake switch).

AJxtcman
03-21-08, 05:24 PM
I think I have done it!

I had something for the dyno runs, but I think I finally got the torque management up to the 90% range on the 2000 to 2003 cars.:thumbsup:

I will post more after I get the 2 feet of snow out of my driveway

CadillacSTS42005
03-21-08, 07:10 PM
hahahaha
snow sucks
but it makes donuts in a FWD STS very possible
hahaha

AJxtcman
03-22-08, 11:45 AM
I have learned so much since I started this thread.

On a 2000 to 2003 FWD Northstar if you turn off the T/C the PCM will reduce the torque output. This is similar in theory to the earlier cars starting in second gear. So don't turn off your T/C!

If a T/C DTC is set the PCM will reduce torque output!

I disconnected the ABS/TC module on a 2003 car and it ran just a tick slower. I thought that it was a fluke. No it was slower. It may have been a .1 of a second, but it was slower. The PCM will set DTC's for open circuits and the PCM does not receive that all important State Of Health (SOH) code from the ABS/TC module.

I tried to test the stall speed in a 2003 DHS. To do this you place the car in gear, apply the brake to hold the car, and mash the gas. The car would rev to 1800 RPM's and then start to drop off. Then if I held it for more than say 5 seconds it would kill cylinders. pretty soon it was 1500 RPM's

When the PCM see a brake pedal input and a TPS angle increase the PCM retard the timing (the first RPM drop) then the PCM shuts off cylinders. Just listen the your exhaust. We figured this out at the track. Try to launch with the gas and brake you really add to your time. Tell the guy running the dyno he can not use the brake and gas!

I made up some 1K resistance connectors for the dyno. We change a few wheel bearings a year. I started to cut the connectors off of the old ones. I soldered in the resistors and then just clipped them on for the dyno. I had no DTC's set or messages, but we only made 200 RWHP. Is this because the ABS and the PCM wheel speed did not match? I am not sure if this caused a reduction in power. I will take a data logger next time.

AJxtcman
03-22-08, 12:44 PM
PCM Torque Reduction Tables

These are the tables inside of the PCM's program!

IAT: Yeah The Intake Air Temp sensor will reduce torque on a Northstar. It will revamp timing and shift speeds. When it is cold out lets just say 30° out and you get that Ice possible message on your DIC. Nail the gas and at 30 MPH, it will only drop into 2nd. If it is 50° out you will get it into 1st gear. If the temp is 90° out the PCM is trying to protect the trans and it reduces more timing on shifts. If the car is hot under the hood say 160° you would get detonation so they pull out timing. If you get some cold air going in to it the PCM will add some back without getting detonation.

IAT Spark Correction vs IAT vs MAP: This is one of the tables used for above

Traction Control Spark Retard vs RPM: This table is the setting for the amount of spark retard at a RPM when the T/C is active.

Traction Control Spark Retard vs Desired % Torque Reduction: This is the factor table for the desired amount of reduction.

Traction Control Aggressive Spark Retard vs RPM: Think of this as when your are on ice.

% Torque Loss vs Spark Retard: This table is the inverse of the other table and tells the PCM how much torque is lost for a given amount of spark retard.


Camel hump Mode: Shut off cylinders to cool the engine

% Torque Reduction When Traction Control Disabled: This is the table for the % reduced when a DTC is set, the T/C is off, no SOH message received, and the PCM receives a message stating that the T/C can not control traction.

I have skipped over a lot. I will add it in later

AJxtcman
03-22-08, 12:48 PM
The 4T80E has a full set of Torque Management Tables also.

I will get them in soon.

codewize
03-23-08, 11:29 PM
AJ you're killing me with all these new threads. I can't keep up. What steps can I take to get more ?

AJxtcman
03-24-08, 07:15 AM
AJ you're killing me with all these new threads. I can't keep up. What steps can I take to get more ?

New?
Post #1 was on 05-18-07, 10:46 AM

codewize
03-24-08, 08:53 AM
OK ok. All this new info and new posts.


New?
Post #1 was on 05-18-07, 10:46 AM

AJxtcman
03-25-08, 06:41 PM
Does everyone understand that I have defeated most of the Torque Management!!!!!!

Proof
-cii7InaulI

I can not pass this information on!
If I did your cars would be tore up!
If you were to get the info what would be the first part to break? Front engine mount!
So you get your self a solid front mount. Then what? You rip the bracket up?
Maybe the trans break and then what? Will it be blamed on me?
I can see an older fella using this just fine. You know that guy that is 68 years old. He pulls up along side a Muskrat at a light. Engages the device and blows the doors off that ford.:eek:
I can see that 21 year old kid nailing the gas on the 100 time and the engine flips over in the engine compartment. :eek:

codewize
03-25-08, 09:29 PM
OK I want it. BUT can it be tamed down to be greater than stock but not to the 'rip things apart ' level'? Or is this on On/Off type thing?

Either way I want one. PM or email me please :) For one, this sounds like I can now dyno my car.

Highline Cady
03-25-08, 09:49 PM
Ya, youngsters would probably tear stuff up. Even being a little older, it's hard not to smoke the tires at every light. I love it though, but AJ has set up the whole car to take more "abuse" than most.

Highline Cady
03-25-08, 09:57 PM
P.S.

Everybody that I've taken for a ride, is absolutely stunned. I'm already looking for new front tires, AJ just put the new 18's on last week. :bouncy:

Track opens in April here, I can't wait to see what she'll turn!!!

codewize
03-25-08, 10:48 PM
If I have to drive all the way to Wisconsin .........

GizmoQ
03-26-08, 02:46 AM
If I have to drive all the way to Wisconsin .........

I'll join in on the convoy and we'll pickup AlBundy when we pass through Chitown.

ejguillot
03-26-08, 05:30 PM
Does everyone understand that I have defeated most of the Torque Management!!!!!!

Proof

I can not pass this information on!
If I did your cars would be tore up!
If you were to get the info what would be the first part to break? Front engine mount!
So you get your self a solid front mount. Then what? You rip the bracket up?
Maybe the trans break and then what? Will it be blamed on me?
I can see an older fella using this just fine. You know that guy that is 68 years old. He pulls up along side a Muskrat at a light. Engages the device and blows the doors off that ford.:eek:
I can see that 21 year old kid nailing the gas on the 100 time and the engine flips over in the engine compartment. :eek:

I want it too, and I'll take mine with the full dose, please! I'll just show some restraint and use it only when necessary to blow by those pesky 6 cylinder sedans. :yup:

darien99
03-26-08, 07:34 PM
What about the '95 cars? I don't think torque is reduced with the traction control disengaged...correct?

I should get a vid of my '95 STS in current state of tune. If I'm not easy on the pedal I'm sending the 18's up in smoke half way through 2nd gear. :cool:

Highline Cady
03-26-08, 09:05 PM
comparing a 95 to anything newer is like comparing apples and oranges. You don't have nearly the headaches us 00-05 OBD2 N* owners have. Or 96-99 for that matter.

On OBD2 cars torque management and/or spark is retarded as soon as you turn off the traction control. You'll turn your best times in these cars leaving the traction control armed. And I have time slips to prove it.

AlBundy
03-26-08, 09:17 PM
I'll join in on the convoy and we'll pickup AlBundy when we pass through Chitown.

:thumbsup:Thanks for keeping me in the loop.:D

darien99
03-26-08, 10:30 PM
comparing a 95 to anything newer is like comparing apples and oranges. You don't have nearly the headaches us 00-05 OBD2 N* owners have. Or 96-99 for that matter.

On OBD2 cars torque management and/or spark is retarded as soon as you turn off the traction control. You'll turn your best times in these cars leaving the traction control armed. And I have time slips to prove it.
That's what I figured, because I got my best times with my TC off on the '95. I know what you guys are goin' through, I have to fight NGC on the newer dodges, which basically pulls timing when it sees the engine accelerating faster than oem. :confused:

Highline Cady
03-26-08, 11:00 PM
Sucks, don't it!!! I guess (some) old people don't like torque steer (on fwd cadys). Or more likely, the manufactures are not making other components strong enough, so the easy way to keep stuff from breaking is in pcm limitations under heavy loads. Truly, they don't build them like they used to, lousy bastards. Just my 2 cents, however.

dkozloski
03-26-08, 11:07 PM
With my '06 AWD STS, if I don't brake torque at all but let the car roll and then nail it, the launch is brutal. In any kind of decent traction conditions there is no wheelspin and no T/C active. It just leaves. I left a guy in a Mustang GT sitting at the light with his chin on his chest. I don't have the nerve to try any neutral drop starts.

dkozloski
03-26-08, 11:15 PM
I remember back when Zora Arkus-Duntov built up a demo L-88 Corvette using an auto transmission he borrowed from Buick. He put some slicks on it, took it to the track, and let every magazine writer in the country take it through the quarter with 7000 RPM neutral drop starts. It made hundreds of runs with no problems and they were all in the low elevens. GM knows how to engineer running gear if they want to.

Highline Cady
03-27-08, 12:00 AM
IF THEY WANT TO. Those days are dead, because they don't have to anymore, they just build in barriers into the factory "tune". What's the first thing tuners do, remove the torque management (gm cars) and it will get you better performance, but why do they put torque management in, why do they retard the timing under certain loads, ect? I think it's because they know the vehicles can't take the power they are putting out without breaking something under warranty time stock, let alone when you start adding power through mods.

Must be cheaper to put limitations into the pcm's than actually building high quality high performance heavy duty transmissions, half shafts ect. Once again just my opinion though, good old days are no more.

AJxtcman
03-27-08, 06:29 AM
With my '06 AWD STS, if I don't brake torque at all but let the car roll and then nail it, the launch is brutal. In any kind of decent traction conditions there is no wheelspin and no T/C active. It just leaves. I left a guy in a Mustang GT sitting at the light with his chin on his chest. I don't have the nerve to try any neutral drop starts.

I told Highline Cady I could out drive him in his car last year on this forum. :histeric: WTF was I thinking. We played around with launching the car. It is a lot faster if you do not use the brake when launching. You can only either the brake or the gas, but not both.

AJxtcman
03-27-08, 10:26 PM
ztnK5e9BSF4

tateos
03-27-08, 10:37 PM
How did you get that echo sound effect in the video? That is cool!

AJxtcman
03-27-08, 11:01 PM
How did you get that echo sound effect in the video? That is cool!

I did nothing. I don't know.

AJxtcman
03-27-08, 11:05 PM
I will post some graph on Saturday. They will be for the Torque output!
after that I will be shipping 3 units out for installation!
You will need to sign a waver. You will need to meet my criteria.

I am only making 3 and they will be in molded plastic. You will destoy the unit before you figure it out.:want:

fubar569
03-28-08, 12:32 AM
I remember back when Zora Arkus-Duntov built up a demo L-88 Corvette using an auto transmission he borrowed from Buick. He put some slicks on it, took it to the track, and let every magazine writer in the country take it through the quarter with 7000 RPM neutral drop starts. It made hundreds of runs with no problems and they were all in the low elevens. GM knows how to engineer running gear if they want to.

i have that article (an original copy)...from motor trend sometime in 1969...titled "The 10 Second Trip"

it was a prototype 1970 ZL-1 motor (never officially released) in a 69/70 vette, with 2 styles of headers for testing, a 1100ish CFM carb, lightly cleaned up heads with valve job, racemaster slicks, rear suspension blocked and a TH400 with 4.88 gearing. fastest time: 10.6 @130+ mph...

codewize
03-28-08, 11:39 AM
LOL :) good call on the waiver AND the moulded plastic.

I will post some graph on Saturday. They will be for the Torque output!
after that I will be shipping 3 units out for installation!
You will need to sign a waver. You will need to meet my criteria.

I am only making 3 and they will be in molded plastic. You will destoy the unit before you figure it out.:want:

AJxtcman
03-28-08, 02:19 PM
I am going to do some datalogging this weekend.
I plan on hard run with TCS on.
Then one with the switch off.
Then one with the system in defeat.
I plan on mapping out Torque Reduction, Torque Output in ft lbs.
I will do some 0 to 100 runs also

dkozloski
03-28-08, 02:46 PM
i have that article (an original copy)...from motor trend sometime in 1969...titled "The 10 Second Trip"

it was a prototype 1970 ZL-1 motor (never officially released) in a 69/70 vette, with 2 styles of headers for testing, a 1100ish CFM carb, lightly cleaned up heads with valve job, racemaster slicks, rear suspension blocked and a TH400 with 4.88 gearing. fastest time: 10.6 @130+ mph...

Back then I was quoted a price of $3600 by the parts manager of the local Chevy dealer for a ZL-1 engine, fan to flywheel. I opted instead for a big journal Z28 302 for $880, fan to flywheel. He sold me engines at his cost because I always had interesting projects. The 302 went in my '66 El Camino and the big block out of the Camino went into the backseat of a '66 Corvair. Chevt always had their stuff for sale across the counter to anybody. The only parts I ever heard of that were restricted were the aluminum bumpers, hoods, and fenders on the 409/427 drag cars.

AJxtcman
03-29-08, 03:24 PM
OK I have some Data Logs.
We ran out of time this morning. I will get the amount of torque graphed in ft lbs. I was looking at too much data at one time and the data and the data is a little choppy. One run we did not go as fast as the others, so I ended up with 0 to 73 MPH graphs.

All three runs were made with WOT and he never backed off.
We made one more with the Traction off, but we had driven through some water before we started. On launch the tires spun and the PCM shut off some cylinder. Bert backed off the gas :bigroll: so it was not a good run. Yes it killed cylinders with the Traction off.

The fastest run was Traction Control ON
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/Tractionon0to75at0.jpg
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/Tractionon0to74at74.jpg

The next fastest was Traction OFF. We had a little tire spin not much
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/Tractionoff0to75at0.jpg
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/Tractionoff0to73at73.jpg

The slowest run was the Traction Defeat.
That is ok we had a ton of wheel spin and that is what I wanted!
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/TractionDefeat0to75at0.jpg
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/TractionDefeat0to75at75.jpg

AJxtcman
03-29-08, 05:44 PM
This is the run with Traction Control on
The start
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/Tractiononinto2ndstart.jpg

The PCM Power output read is 6% at 0mph
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/Tractiononinto2nd6.jpg

The PCM does not show the Traction Control Active, but the ABS/TCS requested the PCM to reduce output by 15%. The Dark Blue line
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/Tractiononinto2nd84.jpg

The Max Torque output read before the 1-2 shift is 86%
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/Tractiononinto2nd86.jpg

On the 1-2 Shift the PCM reduced output to 50% for 2 frames
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/Tractiononinto2nd50.jpg

Output after the shift is completed 87%
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/Tractiononinto2nd87.jpg

AJxtcman
03-29-08, 05:53 PM
This is the run with the Traction Control OFF

The PCM shows 66% power output @ 0 mph
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/TractionOFFinto2nd66.jpg

Max power output before shift 81%
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/TractionOFFinto2nd81.jpg

The PCM shows the power was reduced to 44% on the shift, but for less time.
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/TractionOFFinto2nd44.jpg

The power output went up to 83% after the shift.
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/TractionOFFinto2nd83.jpg

AJxtcman
03-29-08, 06:03 PM
This is the run with the Traction Control Defeated

The PCM reading was 59% power output @ 0 mph
Hey we had a lot of tire spin
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/TractionControlDefeatinto2nd59.jpg

The Max power output before the shift was 82%
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/TractionControlDefeatinto2nd82.jpg

The power was reduced to 46% on the shift
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/TractionControlDefeatinto2nd46.jpg

After the shift the output jumped to 85% This was the last run
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/TractionControlDefeatinto2nd85.jpg

CadillacSTS42005
03-29-08, 06:47 PM
hellooooooo nurse!

CadillacSTS42005
03-29-08, 06:54 PM
A.J.
http://cgi.ebay.com/ebaymotors/2002-Cadillac-Seville-ECM-ECU-Computer_W0QQcmdZViewItemQQ_trksidZp1638Q2em118Q2e l1247QQcategoryZ33596QQihZ002QQitemZ120220038935QQ rdZ1QQsspagenameZWD1V
pcm paid for and will be shipped directly to YOU
soon as you send it out let me know and ill set up a dyno day to test it with my Corsa (curious to see how Corsa really works out) and we can finally put this all to rest...

ill measure the resistance of the wheel speed sensors at work on Tuesday and but appropriate ones to plug into them in the event the car has errors like Codes did on the dyno...

CadillacSTS42005
03-30-08, 02:18 PM
AJ
my PM box is loaded
email me and well talk
thanks bro

AJxtcman
04-04-08, 07:46 AM
OK I have some Data Logs.
We ran out of time this morning. I will get the amount of torque graphed in ft lbs. I was looking at too much data at one time and the data and the data is a little choppy. One run we did not go as fast as the others, so I ended up with 0 to 73 MPH graphs.

All three runs were made with WOT and he never backed off.
We made one more with the Traction off, but we had driven through some water before we started. On launch the tires spun and the PCM shut off some cylinder. Bert backed off the gas :bigroll: so it was not a good run. Yes it killed cylinders with the Traction off.

The fastest run was Traction Control ON
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/Tractionon0to75at0.jpg
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/Tractionon0to74at74.jpg

The next fastest was Traction OFF. We had a little tire spin not much
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/Tractionoff0to75at0.jpg
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/Tractionoff0to73at73.jpg

The slowest run was the Traction Defeat.
That is ok we had a ton of wheel spin and that is what I wanted!
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/TractionDefeat0to75at0.jpg
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/TractionDefeat0to75at75.jpg


I was running some Datalogs from last summer. I came up with 10.377 0 to 73 mph on one run. I did not have time to check more. That would be atleast a 1/2 second off last year.:hmm: :wtf: did I do? :histeric:

Sub I need to show you a picture. I have not taken it yet. Highline Cady really says his car runs stronger. We will talk

AJxtcman
05-08-08, 07:39 PM
STS take a look at this thread

AJxtcman
10-13-08, 09:17 PM
I have some more to add to this, but I need to do some more test

Torque Management,Traction Control Reduced Torque, and Torque Reduction.

Cadillac Information. (Similar to Corvette’s)

96 to 99 Information

Torque Management
Torque Management is a function of the PCM that reduces engine power under certain conditions. Torque management is performed for three reasons:

• To prevent overstress of powertrain components.

• To limit engine power when brakes are applied.

• To prevent damage to the vehicle during certain abusive maneuvers.

The PCM uses manifold vacuum, intake air temperature, spark retard, engine speed, engine coolant temperature, A/C clutch status, and EGR valve position to calculate engine output torque. It then looks at torque converter status, transaxle gear ratio, and brake switch inputs and determines if any torque reduction is required. If torque reduction is required, the PCM retards spark as appropriate to reduce engine torque output. In the case of abusive maneuvers, the PCM may also shut off fuel to certain cylinders to reduce engine power.

There are five instances (listed in the service manual) when engine power reduction is likely to be experienced

• During transaxle upshifts and downshifts.

• Heavy acceleration from a standing start.

• If brakes are applied with moderate to heavy throttle (input supplied by the Extended Travel Brake switch).

• When the driver is performing stress-inducing (abusive) maneuvers such as shifting into gear at high throttle angles.

In the first two instances, the driver is unlikely to even notice the torque management actions. In the other cases, engine power output will be moderate at full throttle.

When the PCM determines that engine power reduction is required, it calculates the amount of spark retard necessary to reduce power by the desired amount. This spark retard is then subtracted from the current spark advance. In the case of abusive maneuvers, the fuel injectors for cylinders 1, 4, 6, and 7 will also be disabled for a period of time.

Traction Control
Traction Control is a function of the PCM and the EBTCM that reduces front wheel slip during acceleration by applying the front brakes and reducing engine power. Refer to Brakes for an explanation of the EBTCMs role in traction control. The PCM continuously sends out a PWM signal that indicates the torque output of the powertrain. This signal, referred to as the Delivered Torque signal, is used by the EBTCM to determine what action is required when it sees the front wheels slipping. The EBTCM may decide to apply the front brakes only or apply the front brakes and request reduced torque output from the powertrain. The EBTCM requests reduced torque using another PWM signal. This signal, referred to as the Desired Torque signal, is used by the PCM to determine if the EBTCM is requesting reduced torque output from the powertrain. If the EBTCM requests reduced torque, the PCM will disable between one and seven fuel injectors to achieve this.

Desired Torque will normally be a 90 percent duty cycle signal to the PCM. When the EBTCM decides to request reduced engine power, it decreases the duty cycle of the Desired Torque signal by the amount of torque reduction required (90 percent duty cycle means no torque reduction, 10 percent duty cycle means 100% torque reduction). The PCM responds by shutting off fuel to one or more cylinders depending on the percent torque reduction requested. The PCM will not shut off any fuel injectors if any of the following conditions are present

• Coolant temperature is below -40°C (-40°F) or above 131°C (268°F).

• A low coolant level is present.

• Engine speed is below 600 rpm

The disabled fuel injectors will be re-enabled one by one as the need for traction control ends.

Several DTCs disable traction control when set. They will also trigger a TRACTION OFF light or message. The PCM traction control override also disables traction control and triggers the message. To diagnose a Traction Off light/message, diagnose any DTCs set first. Then check the traction control override and, if active, deactivate the override. If the TRACTION OFF light/message is still present, refer to Brakes for further diagnosis.

On 96 to 99 FWD Northstar’s when the T/C is turned off the PCM starts the car in second gear to reduce torque output
.
.
PCM

Fuel Shut-Off Mode
The PCM has the ability to completely turn all the injectors Off or selectively turn Off some of the injectors when certain conditions are met. These fuel shut-off modes allow the Northstar powertrain to protect itself from damage and also improve its driveability.

The PCM will disable all eight injectors under the following conditions:

Ignition Off (prevents engine run-on).
Ignition On but no ignition reference signal (prevents flooding or backfiring).
High engine speed (above red line).
High vehicle speed (above rated tire speed).
Extended high speed closed throttle coastdown (reduces emissions and increases engine braking).
The PCM will selectively disable up to four injectors under the following conditions:

Torque Management enabled (transaxle shifts or abusive maneuvers).
Traction Control enabled (in conjunction with front brakes applying).
Low coolant condition (protects engine from overheating).
.
.
.
.
Traction Control System (TCS)

Traction Control
Traction control will not have any effect on the operation of the vehicle until the control module detects one or both of the front wheels rotating faster than the rear wheels. At this time the electronic brake and traction control module (EBTCM) will request the powertrain control module (PCM) to reduce the amount of torque applied to the drive wheels. The PCM does this by retarding timing and selectively turning off fuel injectors (up to a maximum of 5). The EBTCM will apply the front brakes, thus reducing torque to the front wheels. Once the front wheels begin to rotate at the same speed as the rear wheels, the system will return full control to the driver. During the traction control mode, if the brake is applied to only one front wheel, most of the torque from the engine will be directed to the other front wheel which will improve the traction of the vehicle.

The braking is accomplished by closing the TCS master cylinder isolating valves, this isolates the master cylinder from the rest of the system. The TCS Prime valves open to allow the pump to get brake fluid to build pressure for braking. The drive wheel circuit solenoids are energized as needed to allow for pressure hold, pressure increase, or pressure decrease.

The TCS may be deactivated by the driver if desired. In order to deactivate the TCS with the engine running, depress the traction control switch. The system will remain deactivated until the ignition switch is cycled, or the switch is pressed again.

The EBTCM output (Desired Torque signal) is sent to the PCM as an input. When the PCM has a value of 100% the input is a 90 to 95% PWM at 128 hertz signal from the ABS/TC pulled low.
If the PCM has a constant 90% PWM signal. The PCM will not reduce Torque in this part of the program. It can reduce torque from the torque management, but it will not be from wheel spin.
If you add a PWM driver that hold the circuit at the 90 to 95%, but can be switched back to the cars system with a flip of a switch. Then you have a good piggy backed system.

On a 2000 to 2003 FWD Northstar if you turn off the T/C the PCM will reduce the torque output. This is similar in theory to the earlier cars starting in second gear. So don't turn off your T/C!

If a T/C DTC is set the PCM will reduce torque output!

I disconnected the ABS/TC module on a 2003 car and it ran just a tick slower. I thought that it was a fluke. No it was slower. It may have been a .1 of a second, but it was slower. The PCM will set DTC's for open circuits and the PCM does not receive that all important State Of Health (SOH) code from the ABS/TC module.

I tried to test the stall speed in a 2003 DHS. To do this you place the car in gear, apply the brake to hold the car, and mash the gas. The car would rev to 1800 RPM's and then start to drop off. Then if I held it for more than say 5 seconds it would kill cylinders. pretty soon it was 1500 RPM's

When the PCM see a brake pedal input and a TPS angle increase the PCM retard the timing (the first RPM drop) then the PCM shuts off cylinders via injectors. Just listen the your exhaust. We figured this out at the track. Try to launch with the gas and brake you really add to your time. Tell the guy running the dyno he can not use the brake and gas!

I made up some 1K resistance connectors for the dyno. We change a few wheel bearings a year. I started to cut the connectors off of the old ones. I soldered in the resistors and then just clipped them on for the dyno. I had no DTC's set or messages, but we only made 200 RWHP. Is this because the ABS and the PCM wheel speed did not match? I am not sure if this caused a reduction in power. I will take a data logger next time.

Engine Torque Reduction Tables

These are the tables inside of the PCM's program!

IAT:
Yeah The Intake Air Temp sensor will reduce torque on a Northstar. It will revamp timing and shift speeds. When it is cold out lets just say 30° out and you get that Ice possible message on your DIC. Nail the gas and at 30 MPH, it will only drop into 2nd. If it is 50° out you will get it into 1st gear. If the temp is 90° out the PCM is trying to protect the trans and it reduces more timing on shifts. If the car is hot under the hood say 160° you would get detonation so they pull out timing. If you get some cold air going in to it the PCM will add some back without getting detonation.

IAT Spark Correction vs IAT vs MAP:
This is one of the tables used for above


Brake Torque Control:
This will reduce timing, reduce injector pulse, and shut down injectors

AC Clutch Engagement and Release:
This will reduce or increase timing, reduce or increase injector pulse, and reduce or increase IAC counts

TCC Engagement and Release:
This will reduce or increase timing

DTC Torque Reduction:
This can reduce timing, reduce or increase injector pulse, and shut down injectors depending on the DTC set

TCS

Traction Control Spark Retard vs RPM:
This table is the setting for the amount of spark retard at a RPM when the T/C is active.

Traction Control Spark Retard vs Desired % Torque Reduction:
This is the factor table for the desired amount of reduction.

Traction Control Aggressive Spark Retard vs RPM:
Think of this as when your on ice.

% Torque Loss vs Spark Retard:
This table is the reverse of the other table and tells the PCM how much torque is lost for a given amount of spark retard.


% Torque Reduction When Traction Control Disabled:
This is the table for the % reduced when a DTC is set, the T/C is off, no SOH message received, and the PCM receives a message stating that the T/C can not control traction.

Desired Torque Failure Limit:
Number of invalid desired torque reads out of Desired Torque Pass Limit reads which will set a fault.

Desired Torque Pass Limit:
Number of desired torque reads which will set a pass if Desired Torque Failure Limit invalid reads have not been reached.

Traction Control Re-enable Time:
This is the amount of delay before the system return to normal.
When I test have test driven some early CTS’s that have a very long delay. Like I can count 2 thousands before the PCM returns the power.



Engine Protection

Low Engine Oil Pressure:
This will shut off all the injectors and or the Fuel Pump

Camel hump Mode AKA Over Temp:
Shut off cylinders to cool the engine

Over RPM:
This will reduce timing, reduce injector pulse, and shut down injectors

Misfire Balance Timing offset:
Adjusts the timing to prevent damage from internal torsional stress when the engine is misfiring.


Vehicle Protection

Vehicle Over Speed:
Shuts off injectors

Extended Brake Pedal Travel:
This will reduce timing, reduce injector pulse, and shut down injectors

Wheel Speed Sensor Failure:
This can reduce timing, reduce injector pulse, and shut down injectors depending on the system and the VSS

Catalytic Converter Protection

Misfire Detection:
This will reduce timing, reduce injector pulse

Catalytic Converter Over Temp
This will reduce timing and Vehicle Speed (Shuts off injectors), Change Stoich to stabilize converter temp


The 4T80E has a full set of Torque Management Tables also.

Drivetrain Abuse Management:
This will reduce timing, reduce injector pulse, and shut down injectors
Examples: Neutral drops, Over Speed Governor, Trans Slip

Garage Shifts:
Reduces Trans Line Pressure via the trans PCS

Trans Upshift and Downshift Torque Reduction:
Trans PCS change, Shift Timing, Ignition Timing Reduction.

codewize
10-13-08, 10:22 PM
Someone just tell me how to get down the track in the least amount of time. According to this we should make runs with the TC on and the button NOT pushed?

It's all nice to do fancy burn outs but that's not what I want. I want lower ET's period.

mythy
10-13-08, 10:27 PM
now I know why I get the feeling that my Eldorado is slower then my Avengers 2.5L V6. Because it is! :banghead:

Submariner409
10-13-08, 10:53 PM
Read AJ's most recent post and accept the fact that, when it gets down about halfway, opinion and conjecture start to creep in, so it's not clear as to which car does what with which transmission when what button is pushed.

The bottom line is to forget the thread and go to a track with a clean, tuned car and practice ! Your time slip in your car is the answer. Anything else is pure, flat garbage. Every car in the same production run of the same make and model is different. Only you can determine how good or bad different it really is. For me, or anyone else, to tell you that you'll run a 14.25 at 96 is a lie. It's your car. Run it. If you have no baseline, you're lost. For someone to tell you that bolt-on widget A or B is magic is pure speculation. Do your work and run again. Faster ? WOW! Slower ? Whoops......

Ur7x
10-13-08, 10:54 PM
Someone just tell me how to get down the track in the least amount of time. According to this we should make runs with the TC on and the button NOT pushed?

It's all nice to do fancy burn outs but that's not what I want. I want lower ET's period.

Lowest ET? Fastest MPH? Easy
1) Stock PCM
2) load up the torque converter to 2500 RPM
3) TC on and working.

Everything else makes the cars slower.

AJxtcman
10-13-08, 11:26 PM
I don't think you under stand the reasoning for my post.

I am sharing information about the Torque is manipulated by the PCM.

I am not telling you what to do. I am telling you what I am working on.

#1 Brake Torque Abuse. This has NO effect on the VSES system and it will not set DTC's if I alter it. After I change it to my liking you will be able to launch on the brake.

#2 This is to show how the all the different Torque Managements and or Torque Reduction are connected/woven together. (this is for you Sub) :cool:

I am working on a new theory to disable the system. Of course I have a ton of help doing this. I have about 10 people lend time to this. :shhh:

AJxtcman
10-13-08, 11:27 PM
BTW I like to leave on the brake

Ur7x
10-14-08, 12:57 AM
BTW I like to leave on the brake
:rolleyes: Ya "Stomp and go" is so last week...:rolleyes:

AJxtcman
10-14-08, 06:38 AM
:rolleyes: Ya "Stomp and go" is so last week...:rolleyes:

Go to the track and prove me wrong. Leaving on the brake will cause any 2000 to 2005 FWD Northstar to run slower. All of then shut off cylinders.

That is not what this thread is about.

AJxtcman
10-14-08, 06:43 AM
Read AJ's most recent post and accept the fact that, when it gets down about halfway, opinion and conjecture start to creep in, so it's not clear as to which car does what with which transmission when what button is pushed.

The information I supplied is mostly from GM. The information is complied from FSMs, Training Materials, and GM Factory Calibration Information.

I added some of my personal experiences into it also, but very little. GM did not put every thing in the FSM for good reason.

Ur7x
10-14-08, 01:58 PM
BTW I like to leave on the brake


Leaving on the brake will cause any 2000 to 2005 FWD Northstar to run slower.

You are confusing everyone again

Post #1 "I like to leave on the brake" anyone who has been to a track knows that means load up the tranny... But then within 48 hours we get
Post #2 "Leaving on the brake will cause [the car] to run slower"

Which is it?

BTW Codewise has already proven this wrong... he did a stomp and go run and it was a full half second slower in the quarter mile.

AJxtcman
10-14-08, 06:29 PM
You are confusing everyone again

Post #1 "I like to leave on the brake" anyone who has been to a track knows that means load up the tranny... But then within 48 hours we get
Post #2 "Leaving on the brake will cause [the car] to run slower"

Which is it?

BTW Codewise has already proven this wrong... he did a stomp and go run and it was a full half second slower in the quarter mile.

I perfer leaving on the brake. We have found that this is not the fasted way on the FWD Northstar.

AJxtcman
10-14-08, 07:19 PM
OK I have some Data Logs.
We ran out of time this morning. I will get the amount of torque graphed in ft lbs. I was looking at too much data at one time and the data and the data is a little choppy. One run we did not go as fast as the others, so I ended up with 0 to 73 MPH graphs.

All three runs were made with WOT and he never backed off.
We made one more with the Traction off, but we had driven through some water before we started. On launch the tires spun and the PCM shut off some cylinder. Bert backed off the gas :bigroll: so it was not a good run. Yes it killed cylinders with the Traction off.

The fastest run was Traction Control ON
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/Tractionon0to75at0.jpg
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/Tractionon0to74at74.jpg

The next fastest was Traction OFF. We had a little tire spin not much
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/Tractionoff0to75at0.jpg
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/Tractionoff0to73at73.jpg

The slowest run was the Traction Defeat.
That is ok we had a ton of wheel spin and that is what I wanted!
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/TractionDefeat0to75at0.jpg
http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/bert%20testing%20graphs%20after%20converter/TractionDefeat0to75at75.jpg
Take a look at this Picture!
It was cold out and we were trying to spin the wheels to prove a point!!!!!!
I wanted this run to be the slowest!

http://i224.photobucket.com/albums/dd25/AJxtcman/Bert/tread.jpg

Ur7x
10-14-08, 08:30 PM
I perfer leaving on the brake. We have found that this is not the fasted way on the FWD Northstar.

Not true... Codewise's third run was "not on the brake" and it was BY FAR the slowest of the bunch...

The FWD Northstart work best with a "on the brake" aka "prefered" launch

AJxtcman
10-14-08, 09:56 PM
Not true... Codewise's third run was "not on the brake" and it was BY FAR the slowest of the bunch...

The FWD Northstart work best with a "on the brake" aka "prefered" launch

3 runs vs 100+

I have no idea how many at the track and how many on the road.

SLOWnSTEADY
10-21-08, 12:24 PM
AJ.... you are a Fiero.nl member aren't you...?

Either way... how can I get one of these?

AJxtcman
10-21-08, 01:08 PM
AJ.... you are a Fiero.nl member aren't you...?

Either way... how can I get one of these?

Correct and PM sent

codewize
10-21-08, 02:28 PM
Ohhhh AJ has a sexy new avatar :)

AJxtcman
10-21-08, 03:50 PM
Ohhhh AJ has a sexy new avatar :)

I had been looking for sometime and then I had my PC issues. I still want something a little different. A nice little Northstar :thumbsup:

Ur7x
10-21-08, 06:46 PM
Wow!

All three of these last posts (mine included) do nothing to move the discussion forward...

Is it now our goal to clutter up this thread as much as the other one?

If you want to bump the thread... a simple
"bump" or "TTT"
is much more classy

AJxtcman
10-21-08, 11:06 PM
AJ.... you are a Fiero.nl member aren't you...?

Either way... how can I get one of these?


Correct and PM sent


Wow!

All three of these last posts (mine included) do nothing to move the discussion forward...

Is it now our goal to clutter up this thread as much as the other one?

If you want to bump the thread... a simple
"bump" or "TTT"
is much more classy

OK I will read todays post again