: 96 Deville won't idle down, hard start and backfires when cold



magistrate_apeman
01-16-13, 01:52 AM
I just bought this Deville. It has 83k miles. Recent tuneup. When the engine is really cold, it hesitates to start and backfires thru the intake pressure relief valve like a Chevrolet that's out of time a little. Once it starts, it idles rather erratic until it warms up a little, and then it's smooth as butter. Then sometimes the engine wants to idle incredibly high, 1500 to 2000 rpms, no matter whether in Park or driving. I've cleaned the tbi opening and butterfly and cleaned the idle air control. I can't find any vacuum leaks. I think I hear a hiss from the backfire valve behind the power steering pump, but a shot of Gunk doesn't effect the revs at all, and then I'm convinced that it's just the belt and pulley whirring. Sometimes it idles fine, sometimes not. It's not throwing any codes, not misfiring. No horsepower shortage, didn't overheat over the 120 mile drive getting it home. What's going on here? It's a nice old car, but I don't want to start dumping a bunch of money changing parts in hopes of stumbling onto a fix. I've searched this issue extensively via Google and tried all the cleaning and pulling codes and so forth, but to no avail. Any advice would be much appreciated. Thanks...

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I also pulled the line off the fuel pressure regulator and no fuel leaked out.

Submariner409
01-16-13, 10:34 AM
Black magic: Find a 20 oz. jug of Chevron TECHRON and use that in the gas with a fill of 91/93 octane TopTier gasoline. (Google it). If that doesn't clear up the poor cold starts, then you're probably in the fuel injector cleaning business.

When was the last spark plug and plug wire replacement ?? The correct plugs are AC Delco #41-950 Platinum plugs and an AC Delco wireset. Remove the 4 coils and the ICM and clean the contact bases as well as the coil towers. Make very sure the ICM ground wire is securely fastened to the ICM and engine. make sure the plug wires are connected to the proper (GM recommended) coil towers.

For parts, talk to Chris in parts at Rippy Cadillac over there >>> and for parts info and pictures/diagrams use www.rockauto.com (http://www.rockauto.com) and/or www.gmpartsgiant.com (http://www.gmpartsgiant.com) .

magistrate_apeman
01-17-13, 06:07 AM
Complete tuneup was performed, including new plugs and wires, by a Cadillac dealer little over a year ago. That's actually the only service record I have for it. Going to start back in on the car this weekend, beginning with a combustion leak test, fuel pressure test, and an injector leak test that I read about here last night. Also read that a bad tps would cause my high idle issue, though I was convinced that it should have thrown a code were it faulty. Then again, I haven't had opportunity to put any miles on the car aside from the 100+ mile ride home, during which it didn't act up. I'll use the bottle of Techron, too.

How sensitive are these N*'s to fuel grade? I'm quite certain the previous operator (girl in college) wouldn't have paid for premium.

Submariner409
01-17-13, 09:32 AM
The Northstars use a knock sensor to control maximum ignition advance if ping/knock/detonation is detected. While your 1996 engine is spec'd for premium, it will run perfectly well on 87 and 99.9% of the time you'll never feel a performance loss; However, if you intend to pull a trailer, do any mountain driving, or want to operate the car to its maximum potential, use premium fuels. Also, Google "top tier gasoline". Study.

The 2000 and later Northstar is spec'd for 87 octane - combustion chamber shape change, compression ratio dropped from 10.3:1 to 10.0:1 with no performance loss. The manual does the flip of the above - it spec's 87 but says you might want to use premium under the above hard service conditions.

These engines do NOT need a lot of ignition advance to keep the flame travel/combustion pressure in the most efficient part of the power downstroke.

Ranger
01-17-13, 12:24 PM
When the engine is really cold, it hesitates to start and backfires

Once it starts, it idles rather erratic until it warms up a little

Then sometimes the engine wants to idle incredibly high, 1500 to 2000 rpms

I think I hear a hiss from the backfire valve behind the power steering pump

Sometimes it idles fine, sometimes not.
Sounds like a vacuum leak to me.

magistrate_apeman
01-17-13, 01:03 PM
I was thinking vacuum leak, too, but I haven't been able to find one. Would that cause the backfiring and hard start?

Also, can a tps go bad without throwing a code?

What I'm thinking is there's a fuel leak somewheres causing the hard start and backfiring, as well as a bad tps or vacuum leak causing the high idle. I'd planned on working on it this week, but some extra paying work popped up and haven't had time. Going to rent a fuel pressure test kit and a vacuum test kit this weekend. Also going to purchase a combustion leak tester to Check the head gasket fiasco before spending another nickel. This Northstar is a weird rascal.

Ranger
01-17-13, 03:30 PM
Yes, a vacuum will cause a lean condition and can cause backfiring and hard starts. Low fuel pressure could also cause it.

Never heard of a bad TPS not setting a DTC.




I also pulled the line off the fuel pressure regulator and no fuel leaked out.


You might want to try it again and add vacuum this time either with a hand held vacuum pump or buy sucking on the vacuum line. On rare occasions the diaphragm rupture is so small that it takes vacuum added to the fuel pressure to get the fuel to leak.

magistrate_apeman
01-18-13, 08:54 PM
Had a few minutes to tinker today. 40 degrees out, car was a little slow to fire but no backfires or anything. Ran combustion leak test, test fluid never changed colors. In the process, however, if found a few rotten vacuum lines leaking. Replaced the easy one, the other runs down into the right front wheel well. Put a pressure gauge on the fuel system; I'm carrying 40+ pounds of pressure running. However, the pump doesn't kick on when I turn the key on, only when I'm cranking/running the engine. What's up with that? Isn't it supposed to kick on for 3 seconds or so to prime? Drove a few miles to the gas station and car wash, car runs and rides beautifully. Not so concerned about the head gaskets now. And that's as far as I made it. Time to hit the road again.

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Oh, and I changed the fuel pressure regulator, too. Mechanic friend advised it, said that's why my fuel pump isn't priming when I turn the key on. He was wrong.

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And the car has been idling normally for two hours. Warm weather? Yes, I even before the fpr swap.

Ranger
01-18-13, 10:12 PM
Yes, the fuel pump should run for 2-3 seconds at key on. Not sure why yours doesn't.

magistrate_apeman
01-18-13, 10:21 PM
Bad relay? Thanks for all you folks' input, btw.

Ranger
01-18-13, 10:41 PM
I would think if the relay was bad it would not run at all.

magistrate_apeman
01-19-13, 12:01 AM
I read somewheres around here that, in regards to the fuel pump, the key on-engine stopped priming function was completely separate from the engine running function, controlled by two separate components of the computer system. Ring any bells? Convoluted sentence that was, for sure.

magistrate_apeman
01-19-13, 06:46 AM
Found this snippet in the archives, from a fella name of Warren J: "The reason for the long crank time is that there is a secondary power path to the fuel pump. It is provided by the oil pressure switch after the engine has developed sufficient oil pressure. Your engine should start and run even if the fuel pump relay is in your pocket. A code would be set, of course."

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Fiddled with the a/c a little the other day, too, just to see if it would take a charge. Never got the compressor to kick in. Previous owner said it was ice cold. Turns out, the a/c relay is right next to the fuel pump relay. Related? Perhaps. Previous owner also said he had a new wiring harness installed at some point. Don't know which one; no documentation.

Ranger
01-19-13, 11:44 AM
Found this snippet in the archives, from a fella name of Warren J: "The reason for the long crank time is that there is a secondary power path to the fuel pump. It is provided by the oil pressure switch after the engine has developed sufficient oil pressure. Your engine should start and run even if the fuel pump relay is in your pocket. A code would be set, of course.
Not positive, but I think that may have been correct on the earlier cars (prior to yours).

Submariner409
01-19-13, 01:08 PM
His engine/fuel pump does not depend on oil pressure for a 'permission to start' signal from the PCM. As oil pressure in these Northstars builds to over 5 psi the oil pressure sending switch (on the oil filter adapter) OPENS, sending an OFF signal to the PCM which tells it not to turn ON the oil pressure warning light/icon in the DIC. Fuel pump RUN is controlled by engine rpm, ignition signals (CKP, CMP), ignition switch position, and gosh knows what else - but it's not dependent on oil pressure.

At key:ON the ignition switch sends a signal to the PCM which then does the one second fuel pump run/prime sequence. During START the fuel pump relay is held ON and the pump runs - the engine catches, run signals are sent from the PCM, you release the key and the fuel pump runs as long as the engine has rpm. The engine stalls for any reason or you turn OFF the key, the fuel pump relay drops out and the pump stops.

You can completely disconnect the oil pressure sending switch in these cars and it makes no difference in fuel pump operation. Witness the several threads over the past 3 years where members have either broken the switch connector/wires or the switch itself and the car runs just fine with no messages. You just won't see the low oil pressure icon on the DIC - and that only stays on during the DIC prove-out at key:ON - or if the switch goes bad and you get a flickering pressure light.

There are no "rollover" fuel pump safety inertia switches in these cars.

magistrate_apeman
01-19-13, 01:36 PM
My car is a pre-OBDII 96 model. Does that make a difference?

Ranger
01-19-13, 04:11 PM
No. In fact, it might be the 4.9 that had that, but again, I'm not positive. I AM positive that yours does not have that feature.

magistrate_apeman
01-19-13, 04:30 PM
OK. If not a relay, and thoughts as to where I should look? Where are those relays and things, anyhow? I know where the regular fuse box is on the fender well, but I didn't see the other that's mentioned in the manual.

magistrate_apeman
01-19-13, 10:37 PM
Took the girlfriend out this afternoon in the Caddy. Ran beautifully for a while, then the buzzers began buzzing. PC0717, turbine speed sensor. Wonderful. Then it sped up on its own again, briefly, and then settled back down. Gonna try tps swap tomorrow. Then, come Monday, begin hunting for someone to fix that stupid sensor at a reasonable price. BahHumBug.

Submariner409
01-20-13, 11:30 AM
P 0717 is "Input Speed sensor circuit". You might want to open and clean the main transmission wiring harness connector first. Down low below the water pump/water pump cover area.

FWIW, to replace the ISS requires removing the transmission from the car.

The GM cost is a bit over $100 for the sensor and 12 hours labor.

magistrate_apeman
01-20-13, 11:54 AM
Yeah, I've been researching it since last night. Found the part for a whopping $26, but there's no easy fix. Gonna begin interviewing mechanics on Monday. There's a little transmission shop down the road from me that I've got a good relationship with. Hopefully they'll cut me a deal.

Anyone know how to locate the wire and plug in for this sensor on the outside of the transmission? I'm fixing to crawl under the car and check out the air compressor, so maybe I can find it and clean it, just for a laugh...

magistrate_apeman
01-20-13, 09:30 PM
Somehow I missed Submariner's post earlier. I was just under the car and could have checked that harness. I was looking for it on the driver side. Damnit...

Couple questions:

Could the idle air control valve cause my high idle? The car was idling fine earlier. I pulled the iac off to inspect it again, and I gave it a little shot of WD-40 and let it sit. Is the rod supposed to have any travel or wiggle? Anyhow, I reinstalled it, started the car and it wouldn't idle down again. Throttle body is spit-shined, including the hole for the iac.

Looked at the air compressor and rear shocks. They're pretty rusty looking and the passenger side has a broken airline. The compressor makes a lot of racket and looks like a pain in the rear. Question is, if I purchase and install the Monroe conversion kits 90008 and 90009, will I still constantly get the annoying "service ride control" message?

Ranger
01-20-13, 10:27 PM
Could the idle air control valve cause my high idle?

Yes. It is an air bypass circuit. The valve controls the amount of air bypassing the closed throttle plate. Is the plunger in good condition?



Is the rod supposed to have any travel or wiggle?
It moves in and out to control air flow. Not sure if there is any wiggle to it or not though. Never had to pull mine.

Submariner409
01-20-13, 10:57 PM
The transmission connector IS on the rear (driver's) end of the engine. So is the water pump and the water pump drive system/thermostat.

magistrate_apeman
01-21-13, 03:01 AM
Hahaha. I thought the water pump was on the passenger side wrapped up in all that accessory drive mess.

My iac plunger doesn't move in and out at all by hand.

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Let me rephrase that. The iac did wiggle a little, but there was no throw. The plunger didn't slide in and out at all, it just had a slight bit of slop in it, it felt.

magistrate_apeman
01-21-13, 08:05 AM
And what if I wanted to install a new air compressor; could I install new non electric air shocks and get rid of the "service ride" message?

Submariner409
01-21-13, 11:18 AM
Either install the new compressor assembly and repair the air lines - cross your fingers for the shocks - they're expensive, OR look in the Monroe catalog for new shocks with air bladders - you can run the air lines/valves (like tire valves) into the trunk and manually control rear ride height.

You need to do some resistor work in the shock electrical connectors to get rid of the suspension system messages.

Down in Cadilac Tech Tips or in one of the many threads in this forum over the past year. Google "cadillac forums 1996 deville suspension height control" or similar, always using "cadillac forums .........................." in the request.

Ranger
01-21-13, 12:37 PM
My iac plunger doesn't move in and out at all by hand.

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Let me rephrase that. The iac did wiggle a little, but there was no throw. The plunger didn't slide in and out at all, it just had a slight bit of slop in it, it felt.
It's not supposed to move by hand. It is electronically controlled and operated.

magistrate_apeman
01-22-13, 03:06 AM
These worth a darn? They come with resistors and whatnot, and allow me to keep my leveling system. $316 for the pair with free shipping on amazon: https://www.arnottindustries.com/part_CADILLAC_yid6_pid28_gid110.html

magistrate_apeman
01-22-13, 10:52 AM
Monroe's tech support emailed me and said their suspension packages include instructions for disabling the dash messages, too.

Ranger
01-22-13, 12:25 PM
The shocks in the link in post #29 are for converting active to passive. You do not need that on a '96 base Deville. You already have passive suspension. All you need is regular shocks with air.

http://www.amazon.com/Monroe-40046-Rear-Shock-Absorber/dp/B0047D9TS0/ref=au_pf_pfg_s?ie=UTF8&Make=Cadillac|46&Model=DeVille|406&Year=1996|1996&carId=001&n=15684181&newCar=1&s=automotive&vehicleType=automotive
http://ecx.images-amazon.com/images/I/31TUnZD%2B6ML._AA300_.jpg

magistrate_apeman
01-22-13, 12:38 PM
Help me out here, Ranger. My 94 Deville had me baffled, too. It, like my current 96, had wires coming from the shocks and struts. What are those wires for if the shocks aren't electronic, and what do I do with them?

Dropping 96 off at transmission shop tonight. $765 labor to change that turbine speed sensor. Wiring harness looks like new. Financially, I'd have been better off leaving this car where I found it. But, it'll be a heck of a nice car and surely dependable after this initial beating, so what the hell... Why not. Better than paying top dollar for a car you believe to need nothing and then getting walloped.

Ranger
01-22-13, 12:55 PM
If you have wires to the shocks then you must have a special ordered car with the CVRSS option (active suspension). That being the case, disregard post #31.

magistrate_apeman
01-22-13, 01:03 PM
Toward the bottom of the shocks, facing in, there's a tube with wires coming out. My 94 was a base with the 4.9L engine and it also had wires coming from the shocks and struts. Never had to monkey with them, though, cause they all worked.

magistrate_apeman
01-30-13, 09:25 AM
Pulled an IAC valve from the junkyard. No effect on idle issue. Warmer and humid here now, and car exhibits high, surging idle issue upon every cold start. Learned a little trick, though. If I shut the engine off and restart it 3 times, it will idle and run fine until it sits and cools off again. Any thoughts?

Ranger
01-30-13, 12:35 PM
:noidea: I'm still leaning towards a vacuum leak.

magistrate_apeman
01-30-13, 12:50 PM
Intake gaskets are cheap...

magistrate_apeman
01-30-13, 05:06 PM
Just talked to a friend at a Chevrolet dealership, and he advised me to grab a junkyard MAFS and see if that makes a difference. Apparently they had some trouble with them boogering up and not throwing codes in the past.

Ranger
01-30-13, 10:22 PM
Never heard of that, but certainly a possibility and can't hurt.

magistrate_apeman
02-07-13, 06:32 PM
Where's this at: Code IP2128 Throttle/Pedal Pos Sensor/Switch E Circ High Input

Ranger
02-07-13, 10:39 PM
IP is not a code. It means Instrument Panel. You probably mean P2128 - Accelerator Pedal Position (APP) Sensor 2 Circuit High Voltage. I've heard of a TPS (Throttle Position Sensor), but never heard of that sensor.

magistrate_apeman
02-08-13, 08:47 AM
It's the category directly after PMC. The code reads IP2128, which I couldn't find a definition for anywhere. The few times one does see that code in a Google search, the "I" us dropped, leaving P2128, which is the accelerator peddle sensor.

It was in the history, and it's obviously not common, so it's probably nothing.

Anyway, my throttle issue seems to have pretty well resolved itself. Since I went to the junkyard and picked up another MAF sensor, the car hasn't acted up. Must have scared it or something.

Now I'm down to an annoying "door open" alarm, which I believe I've narrowed down to the front passenger door latch. And also a clunky air compressor throwing an exhaust valve code, which is getting addressed this morning.

Submariner409
02-08-13, 01:01 PM
The ELC exhaust valve code will probably turn out to be a damaged solenoid control head on the compressor - that system supplies and vents air to/from the shock bladders to control ride height. The head gets gunked up with watery snot from carryover due to an overloaded filter-dryer canister. Replace the entire compressor/control head/filter-dryer assembly. The Suncore website.

magistrate_apeman
02-08-13, 08:26 PM
I got a new compressor from Arnott. They seem like a good company to deal with. A few shops here locally highly recommend them. Didn't get the compressor changed out. Mechanic had a death in the family this morn. I really need a lift, even if it's out in the weather

magistrate_apeman
02-19-13, 06:10 PM
Compressor is on and works swell. No air leaks. Do have an rsoo28 code, hoping it's a wire.

In other news, my throttle body began sticking a few days ago. Tore it all apart and cleaned it last night and installed new gaskets. No more sticky accelerator, but now my high idle issue is back to square one - not idling down below 1500 rpms, just like the day after I brought it home. Last night, after it began idling high again, I swapped the iac valve out again and it idled down to normal. This morning, the temperature dropped to 23 from 45 last night, and now it refuses to idle below 1500. Cycling the ignition and removing wires from components has zero effect. Sooo, I've got a brand new iac valve on the way, even though I'm convinced it won't fix the issue. After that, not sure what to do other than have the intake manifold gaskets changed.

Grey hairs are sprouting at an alarming rate. For two weeks the thing ran perfect and it was wonderful. Why isn't it throwing a doggone code?! Show me a frickin sign already.... This issue is posted all over the net, but no one seems to have a solution.

Ranger
02-19-13, 09:51 PM
Spray some Brakleen around every possible vacuum leak point (incl manifold mounting and the over pressure relief valve). Listen for an RPM increase.

magistrate_apeman
02-20-13, 08:11 PM
Received new iac valve. It came in the wide open position. Installed, now car revs immediately to 3000 rpms.

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Pulled irc plunger out by hand. Plugged it in while in hand with key on, and the unit pulses and vibrates against pressure applied to the plunger, but doesn't noticeably draw in and out. Checked two old iac valves the same way, and they reacted similarly. Reinstalled new iac with plunger pulled out. Idle back to 1500. $60 wasted. Lost.

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Also sprayed carb cleaner around intake and any vacuum lines I could find... Nothing. Disconnected some vacuum lines while car was running, no drastic changes.

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Disconnecting the tps gets the idle down to 1175

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Pulled the air intake line off the mafs housing, then gradually choked off the engine's air, and now it's idling smoothly at 750.

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Plug the tps back in, and it goes wild again.

magistrate_apeman
02-20-13, 10:34 PM
Installed another new tps, and now the car seems back to normal. Grrrrrrrrrrr

magistrate_apeman
02-20-13, 11:40 PM
No more unbranded Autozone junk for me. Car is running fine again.

magistrate_apeman
04-08-13, 10:52 PM
Anyone know what would cause me Deville to start shifting into overdrive too early, and shifting frequently between drive and overdrive while trying to maintain a steady speed between 50 and 60? Please tell me it's something simple like a shift solenoid accessible thru the pan. Please please please. No codes and the car has been running great.

stoveguyy
04-09-13, 10:55 AM
Hmm, my car goes into OD at 45mph and never drops down to 3rd. I have 3.7 final drive though. I assume urs is 3.1 or so?

magistrate_apeman
04-09-13, 11:03 AM
I don't know, stoveguy. Where would I look for that particular info?

Ranger
04-09-13, 12:50 PM
The '96 Deville has an LD8 motor so it is teamed with the 3.11 final drive. When it shifts into OD (4th gear) will vary depending on load. TCC lock up is at 41 MPH, but it will also vary with load. Neither should toggle back and forth while at a steady cruise speed. Not sure what would cause that though.

First thing you need to clarify is are you talking about OD or the TCC?

stoveguyy
04-09-13, 01:08 PM
Yes, most folks cannot tell when tcc drops off since its only 2-300 rpm. BUT u will notice OD dropping off. Hwy cruise is 2k? Jumping up to 2800rpm WILL get ur attention.

magistrate_apeman
04-09-13, 09:51 PM
Stopped and talked to a transmission guy I know (who unfortunately refuses to touch a Northstar equipped machine) and he says the torque converter is dropping in and out of lockup for some reason, not shifting from drive to od as I originally claimed. As ranger says, the issue begins at 41mph. Doesn't seem to do it much if at all with cruise control engaged, but is very noticeable when trying to maintain speed between 41 and 60 via foot. Further thoughts? Simple solution, perchance?

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Could a faulty brake light switch cause this issue? I noticed a few days ago that all my lights had started dimming when I apply the brake pedal, and just now I've begun getting a funky clicking noise from the brake pedal. Also, I can hear an obvious load being put on the engine when I depress the pedal.

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AND, the switch only clicks funky when in park with the engine idling. AND, my trip odometer and fuel mileage gauge reset on their own after reaching around 300 miles, if that means anything.

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AHA! http://www.amazon.com/gp/product/B000EQL13U?ie=UTF8&force-full-site=1&ref_=aw_bottom_links

Ranger
04-09-13, 11:20 PM
The brake switch disengages the TCC so it could be the problem. Might check it first to be sure it is seated properly.

magistrate_apeman
04-09-13, 11:34 PM
It looks different than any other brake switch I've changed. Surely it's fairly straight forward. For $7 I just ordered a new one. I'll let you know what happens.

magistrate_apeman
04-10-13, 11:11 AM
It also seems my doors locks have stopped automatically unlocking when I put the car in park.

CadillacLuke24
04-10-13, 02:47 PM
It also seems my doors locks have stopped automatically unlocking when I put the car in park.

That points to your neutral safety switch. Pull your codes, I'd bet you have a P1520.

magistrate_apeman
04-14-13, 07:06 PM
Stoplight switch didn't fix it. Darn. But, my lights no longer dim when I apply the brakes. Still no codes.

magistrate_apeman
04-15-13, 01:08 PM
Wait a minute. Just checked me codes again and I do indeed have an IP1552 in history, as well as an IP2128 that I didn't catch before. Would those have anything to do with me torque converter?

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Whoops. 1552 is KAM... I had the battery out fer a day. 2128 is tps over voltage. Surely I don't have yet another bad tps. Although that would explain the tcc.

Ranger
04-15-13, 04:05 PM
KAM is simply because the battery was removed. It has no effect. TPS over voltage might be another story though.

magistrate_apeman
04-15-13, 04:12 PM
Checked tps with a multimeter. No dead spots, and wiring harness is carrying 5 volts. What next...

magistrate_apeman
04-20-13, 09:33 AM
Now tps is definitely acting up again. Car not wanting to idle down until I cycle the ignition 3 times. Ordered a Delco unit, will be here some time today. Now, did I get 2 bad autozone units that both gave out within 1000 miles, or is my car roasting them somehow?

Ranger
04-20-13, 11:41 AM
Anything from AutoZone is questionable.

magistrate_apeman
04-20-13, 11:57 AM
Indeed. I normally steer clear of all autozone branded electronics, including starters and alternators, but I gave in on the tps because I was in a hurry. Came with a lifetime warranty, but given its a pain in the arse to change, I give up. I've found that I can usually buy genuine Delco and Delphi parts from Amazon for close to the same money as lower quality aftermarket parts. Free shipping via a Prime account helps. I only wish my local GM dealerships wouldn't attempt to fleece me every time I would like to purchase a part from them. oh well. New Delco tps will arrive today. Cost me $46 including overnight Saturday delivery shipping.

Ranger
04-20-13, 09:57 PM
You must consider that anything with a lifetime warranty must be cheap to produce and a lifetime warranty is fine on easy to change parts. Not so much on the PITA ones.

magistrate_apeman
04-22-13, 06:41 PM
Couple questions:

What is code ip1552? Pops up intermittently in history.

What is IRC in diagnostics? I always get NO IRC DATA.

New tps didn't fix. Car still acting funky. Still have tcc issue, intermittently. Brake fluid switch light now coming on intermittently, even though I've changes that sensor twice with junkyard parts. Trip odometer and avg fuel mileage still resetting here and there. Thinking this is all electrical. Ecm, pcm, something. Maybe a harness with a bad connection.

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Also, when I plug in my bluetooth obdii adapter and run a scan using an app on me android phone, it makes my car shutter. And, some of the voltage readouts bounce around, which I originally attributed to the cheap adapter and software.

magistrate_apeman
04-22-13, 07:42 PM
Tried to run a full diagnostic scan using Torque Pro, but it kept endlessly refreshing, while the car sputtered and began to overheat. So I cut it short, not getting any info, and cleared the car's computer. Restarted the car and it cooled right back down is running smoothly again.

Ranger
04-22-13, 10:18 PM
IRC (Integrated Radio Module)

Code definitions are in the links in the DTC Sticky.