: 94 Eldorado Idle problem



LockDown
03-28-09, 11:05 AM
I'm hoping someone here can help me. I've got a 1994 Eldorado Touring, love the hell out of the car, but have a bad problem.

When in park, the idle jumps up and down, from 2500rpm to almost to where it dies, sometimes dying.

When in drive, it does the same thing, and wants to lurch forward.

I replaced the plugs and wires, that didn't make a difference. I brought it to Midas and had them run error codes, and they got back 8 codes and told me they didn't know what the problem was.

Help? Thanks!

Sorry for posting this twice, I didn't know if I posted in the right forum before. Thanks!

Ranger
03-28-09, 11:44 AM
You might want to pull the DTC's and look them up. Post the DTC & the description. I was going to suggest the ISC motor, but if it is also happening while driving, that would rule out the ISC. I'd start checking for vacuum leaks.

LockDown
03-28-09, 11:51 AM
Thanks Ranger, I was just looking up the cost on the ISC after digging through the forums. When in drive now, the car almost wants to lurch forward while the idle is jumping around as well. I had Midas check for a vac leak when I was there and they told me I didn't have one. They gave me 7 error codes, which are in the car currently at my buddies house who's tearing it apart.

I'll call him and get the error codes. He's considering it a challenge to fix, I'm considering it driving me nuts having to drive the wife's minivan...lol.

LockDown
03-28-09, 11:57 AM
Ok, got the codes...

The first 5 start with P00

P0023, 25, 52, 83, 95, and the last one is P0109.

I tried looking up the error codes in a GM database, but couldn't determine what type engine it was exactly. As you can tell I'm not a mechanic, so the help here is very appreciated.

LockDown
03-28-09, 12:18 PM
Through searching the forums here, damn this is a great site, I will be donating....

P023 (E023) ..................... Electronic Spark Timing (EST) Signal problem [EGR]
P025 (E025) .................. (Ignition Control Module) 24x Reference Low Indicator
P052 (E052) .................................................. ..... PCM Memory Reset
P083 (E083) .................................. Crankshaft to Ignition Module Failure
P095 (E095) .................................................. Engine Stall Detected
P109 (E109) ....... Keep Alive Memory (KAM) Reset/PCM has lost primary battery power

Ranger
03-28-09, 02:17 PM
I'm sure your problem lies in the P023, P025 and/or P085, but I think you're gonna need a FSM by Helm Inc. (not Chiltons or Haynes), unless someone who has one chimes in. Ebay is your friend.

LockDown
03-28-09, 02:59 PM
Thanks for getting back to me, if anyone has any other suggestions, please feel free!

Ranger
03-28-09, 09:18 PM
You might try pulling and cleaning the EGR pintle valve and TB. Be sure to open the manifold and rod out the EGR "mouse holes".

LockDown
03-30-09, 09:30 AM
I replaced the Idle Control Motor, adjusting it until it was idling perfectly when in park, and also replaced the fuel filter, this seemed to fix the problem.

On my way into work, while in drive slowing down to a stop at a stop sign, the car seemed to want to die, the check engine light would flash on, and as soon as I started to drive again it would be fine. The voltage is good, brand new battery and alternator is working good. Any ideas on that? Thanks!

Ranger
03-30-09, 11:40 AM
How did you adjust the ISC motor?

LockDown
03-30-09, 05:18 PM
We adjusted the screw slightly each time until it was idling inbetween 500 and 1000 rpm while in park. The problem I found is intermittent though, I didn't have any problem on the way home, but any suggestions are great. Thanks!

Ranger
03-30-09, 07:14 PM
Press on the plunger and it should retract. Unplug it when it bottoms out. Idle will drop to about 450 and may stall. Now adjust the plunger so that it has a .060 gap.

32vmonte
03-30-09, 10:04 PM
Wait so you can adjust that motor that runs your idle? My N* had a high idle at times and then would idle down once in awhile. Isn't there an idle learn process or something? Then it adjusts its self

Submariner409
03-30-09, 10:16 PM
32v, Different car, different engine from yours.....different idle speed controls.

OOOOOOOOOPPPPPPPPPPSSSSSSSSSS!!!!!!!!!!!.......You 're running a 97 package in a Monte Carlo, right ???? All bets are off.

Ranger
03-30-09, 10:26 PM
Remember, the PCM controls the idle via the ISC motor. The adjustment just assures that it is in sync with what the PCM is telling it. That is for pre '97's I think. In '97 (maybe '96) they went to the IAC valve for idle control.

32vmonte
03-31-09, 01:12 AM
I have a very strange setup I think, I have a 95 Monte, with a 95 throttle body, on a 96 STS motor, and a 94 throttle cable mounting bracket and ISC motor.

Is there anyway that I can upgrade to a IAC style type throttle body, the way this one is set up my gas peddle moves when the motor is cold. I am willing to bet that it is not adjusted correctly.

And plus the sounds of a IAC seems better than this odd setup.

What kind of wiring would be involved if possible?

Ranger
03-31-09, 10:41 AM
Wow! What a conglomeration. You certainly would need a new TB, but I don't know about the PCM.

EscaladePatrick
06-25-10, 05:16 PM
Through searching the forums here, damn this is a great site, I will be donating....

P023 (E023) ..................... Electronic Spark Timing (EST) Signal problem [EGR]
P025 (E025) .................. (Ignition Control Module) 24x Reference Low Indicator
P052 (E052) .................................................. ..... PCM Memory Reset
P083 (E083) .................................. Crankshaft to Ignition Module Failure
P095 (E095) .................................................. Engine Stall Detected
P109 (E109) ....... Keep Alive Memory (KAM) Reset/PCM has lost primary battery power

I have the same exact DTC's as you. Please tell me how you fixed the problem.

Necrosan
06-27-10, 07:51 PM
P023 has nothing to do with the EGR valve... Bad labeling.
You might have a failing ICM (Ignition Control Module).
I would pull off each coil pack and clean the connectors, and also clean the ICMs connectors.
My car gets this exact same code sometimes, and I can assure you - it has _NOTHING_ to do with the EGR valve.
Car will drive all crazy, random RPM fluctuations, etc. Cleaning ICM terminals & coil packs up seems to have fixed it.. Knock on wood.
Good luck!

EscaladePatrick
06-28-10, 10:30 PM
I had the ICM tested and I cleaned the contacts as well and everything with that is good.

Hawker8xp
08-03-10, 04:57 PM
I have a 95 Seville STS with the same problem, we replaced the computer and everything was back to normal. I am told the sometimes go bad.