: 93 N* rough idle, no codes, loss power



pimpjuice01
01-05-07, 03:23 AM
Out of the blue my car started to idle rough and takeoff really bad, with loss of power. On top of that I noticed a bad smell, like something was burning. A week or two later, I changed the plugs because they were well overdue but not the wires. The car ran fine for a while, but now I'm noticing the same problems again. You can notice the engine vibrating, and you can see it in the rear view mirror because it shakes a bit.

Could it be from old plug wires?

I will change them soon, but I'm wondering if there is anything else that could be causing the issues.

THANKS

Ranger
01-05-07, 10:44 AM
Could well be the wires. How about the EGR valve and "mouse holes" in the manifold? Have you cleaned those?

pimpjuice01
01-05-07, 06:42 PM
I'm not too sure about these mouse holes, but I bought that intake manifold cleaner. Ran the engine and sprayed some in while given it gas, also I cleaned my air filter too since I took it off. It seems to idle nice in park, but now in drive you can see it rough. The power loss is intermitten, I can be driving then feel a boosts of power then it'll disappear.

Also I gave it full throttle the other day, then I got this really odd smell after that. Like burning rubber or something? ODD

Ranger
01-05-07, 07:01 PM
Sparying manifold cleaner through the Tb while running will not clean the TB. With the engine off, hold the throttle plate wide open and you'll see the carbon build up on the TB walls and the backside & perimiter of the throttle plate. You need to scrub that off with a toothbrush & rag til clean. The mouse holes are under the intake manifold cover on a '93. Rod them out with a coat hanger or such if they are caked with carbon.

pimpjuice01
01-05-07, 07:40 PM
I did open the throttle plate and sprayed a bunch of intake cleaner, there was not much dirt but it sure got rid of it.... I'll have to look for these mouse holes, I'm not very mechanically inclined but I was able to do the spark plugs on my own. Are they really visible to see?
Would that cause the odd smell?

Ranger
01-05-07, 07:51 PM
Not sure about the smell. When you take the intake cover off, the "mouse holes" should be pretty evident. DO NOT over torque the manifold when reinstalling. Follow the FSM torque specs. If you do not have a FSM, someone else will have to provide the specs.

pimpjuice01
01-14-07, 07:12 PM
ok wellll.
I changed plugs/wires and sprayed the intake cleaner also opened up the throttle plate while cleaning. When you describe taking the intake cover off, how exactly do you get at that?

Do you get at these mouse holes by taking the engine cover off?
I bet I have about hundred people laughing at me right how hahaa

pimpjuice01
01-14-07, 07:16 PM
Another note that might help is.. I'll be crusing at a steady speed then the car will just start making a low vibration, very noticable and sounds pretty bad. I have to let go of the gas to get rid of the problem
*still no engine codes*
Rough idle intermittent
On takeoff sometimes you can feel the power come and go

Ranger
01-14-07, 09:28 PM
Don't just spray the TB & throttle plate, scrub it til all the carbon is off.

Yeah, just remove the intake cover. 4 bolts if I remember correctly. The EGR passages (mouse holes) are inside. DO NOT attempt to start the engine with that cover off.

pimpjuice01
01-18-07, 08:45 PM
I checked my codes and I'm getting PO99 and PO70
P099 (E099) ................ Cruise Control Servo Applied, Not in Cruise
P070 (E070) ................................................ Intermittent TPS Signal

They are codes that are not on, but saved.

Could any of those cause the rough idle/takeoff this is now constant, with the same odd scent. Running rich maybe, because I"m getting half my mileage :(

jss
01-19-07, 08:32 AM
pimpjuice, I had similar symptoms on my 94 Northstar some months back. She'd idle rough sometimes and sometimes not. On accelleration you could feel just a little bit of power coming and going.

On mine it was obvious that she was missing on one cylinder. As my plugs and wires have 92k on them, I first looked at all of the connections between the plug wires and the coils. Two of them were very corroded. I wash the engine once or twice a year and water managed to get underneath the rubber.

I cleaned the connecting surfaces on the coils and wires on the two effected connections. That solved my problem.

Good luck.

pimpjuice01
01-20-07, 12:34 AM
Hmmm, I changed the wires about a week ago and didn't really notice any bad/corroded connection but I'll have to double check since I never paid special attention.. I'm just curious about this ODD smell everytime the car decides to start running shitty again. Just today it was running great, then I floored it to pass someone and it went to crap again :(

pimpjuice01
01-22-07, 11:18 PM
Now I'm getting, but not turning the engine light on..
P030 (E030) .................................................. . ISC RPM out of range
I cleaned the EGR valve, not sure if I cleaned it properly though. There was two holes, one had a piece that moves in and out.. Engine still idling rough, you can see the engine shake a bit and the exhause sounds bad.

jackc
01-23-07, 09:56 AM
Sounds like a bad coil. The smell is unburned gas going through the cat.

I've had to replace 2 coils over the past several months in my 93 to fix problems very similar to yours.

Your car has an on-board diagnostic test that lets you isolate dead cylinders. It does this by letting you turn off fuel to 1 cylinder at a time. If a cylinder is ok, the idle will drop when you turn the fuel off. If it is bad, there will be no change.

To access it, activate the OBD system with the engine idling in park by pressing and holding the Off and Warmer buttons on the climate control. Wait til the DIC blinks and release.

The DIC will run through the display of current codes and codes stored in history. When its done with that, it will say PCM? Press the high blower switch to say yes.

Then it will offer PS01 - say no by pressing low blower. Also say no to PS02 and PS 03. When it offers PS04, say yes by hitting high blower. The idle will increase. You're now ready to kill cylinders one at a time. You're on cylinder 1 now. Press the cooler button to turn off fuel to cyl #1. Watch the tach and listen to the engine while you hold the cooler button down. If #1 is ok, the idle will drop almost imperceptably. The change is subtle. Try it a few times to get a feel for it. You can then switch to cyl #2 by pressing the warmer button. Press the cooler button again. Repeat for all cylinders.

If you have a bad coil, you will find 2 cylinders where killing them makes no difference in the idle. They will share the same coil.

To exit out of this test, turn the key off. Everything will be back to normal when you restart.

As for the ISC code, you may have boogered something while messing with the EGR. Check connections and installation.

pimpjuice01
01-23-07, 11:29 AM
hmmmm thanks... I'll have to try that, I was getting worried that I might have to take it to some scam mechanic. I was hoping it didn't have compression problems, I was going to do a compressions check. Also, was thinking it could be a fuel filter.

jackc
01-23-07, 12:30 PM
I may have left out a step. After you select PCM?, you want to select Overrides. I think its about the 3rd or 4th choice it will give you.

After you've selected PCM, say no (press low blower) until it offers Overrides. Then say yes (hi blower). Then it should offer PS01, PS02, etc...

If you can't make this work, do a search on Power Balance Test. Someone else may have posted the full sequence of steps.

pimpjuice01
01-23-07, 07:32 PM
ok this was the results which were weird....

so I started at cylinder 1 of course... held the cooler button and yes I did notice the idle drop a little..

Cyl 2 - no drop
cyl 3 - a drop, then it came back
cyl 4 - no drop
cyl 5 - drop, and came up
cyl 6 " "
cyl 7 " "
cyl 8 " "

So I don't know if all my coils are messing up, or I'm not doing it right??

jackc
01-23-07, 10:06 PM
OK - this is attempt 3 to respond tonight. Hopefully all 3 won't show up tomorrow.....

This says that 2 and 4 are your problem cylinders. They are on separate coils, so that blows my coil theory.

You say you've changed the wires. How about the plugs?

You may want to go ahead and compression test these 2 cylinders. Its probably ok, but you can rule it out.... Pull the 2 ignition fuses in the fusebox under the hood to keep it from starting while you crank it to test.

How many miles are on this car?

pimpjuice01
01-23-07, 10:39 PM
ok ok I wrote it wrong
210,000 KM
maintained really well too.

ok ok 2/5 were the ones that didn't drop, and from your input and that research I did they're on the same coil. Not 2/4 my mistake. It's looking really good now :highfive:

Wonder why no engine codes!
Here is a pic of the car you saved for me
http://memimage.cardomain.net/member_images/4/web/400000-400999/400770_18_full.jpg

jackc
01-24-07, 09:03 AM
Cool! Put a coil on it. Should run $40 to $60.

Coil output to the plug is not monitored by the computer, so it won't throw a code.

Let me know what happens.

pimpjuice01
01-25-07, 09:38 PM
ALRIGHT so now I Get two coils (just in case)... I put it in thinking everything is going to be fine BUT BAM!!!!! the car is the exact same. I tested the coils, and the posts for voltage or arch but got NOTHING. So somehow the coil for cyl 2/5 is not getting any power? I'm guessing is, where do the coils get power from and are each one on a seperate source??? Maybe the piece where the coils rest on is having problem whatever that is called?

CADILLAC EXPERTS PLSSSSS HELP

Ranger
01-25-07, 09:51 PM
ALRIGHT so now I Get two coils (just in case)... I put it in thinking everything is going to be fine BUT BAM!!!!! the car is the exact same. I tested the coils, and the posts for voltage or arch but got NOTHING. So somehow the coil for cyl 2/5 is not getting any power? I'm guessing is, where do the coils get power from and are each one on a seperate source??? Maybe the piece where the coils rest on is having problem whatever that is called?

CADILLAC EXPERTS PLSSSSS HELP
That is the ICM (Ignition Control Module)

pimpjuice01
01-25-07, 10:03 PM
Really..... Well thats easy to change, but hopefully thats the problem.

Is it common for a ICM to messs up on one coil? Plus it started gradually too :S
I got quotes from Cadillac 513$ thats with my discount

Ranger
01-25-07, 10:12 PM
I don't think it is "common". Before spending that kind of money on one, I'd get a FSM and find the procedure to test it.

clarkz71
01-29-07, 03:06 PM
Really..... Well thats easy to change, but hopefully thats the problem.

Is it common for a ICM to messs up on one coil? Plus it started gradually too :S
I got quotes from Cadillac 513$ thats with my discount

Here's a GM dealer on e-bay, $325 for that module with FREE shipping.


http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&ih=019&sspagename=STRK%3AMEWA%3AIT&viewitem=&item=290006968507&rd=1&rd=1

pimpjuice01
01-30-07, 09:28 PM
OK EVERYBODY THAT HELPED

The problem is fixed after the ICM was replaced :) :)

Ranger
01-30-07, 09:33 PM
Great :thumbsup:

jackc
01-31-07, 01:17 PM
Glad to hear that! I'm sorry that I led you astray on the coil....