running rough
Thread Starter
Melting Slicks
Joined: Feb 2005
Posts: 2,135
Likes: 0
From: Sebastian Florida
St. Jude Donor '06
running rough
My car started running rough a couple of weeks ago, first I thought it was from a grounding strap that was not connected when my tranny was rebuilt. Here are the symtoms, when the car warms up it starts running real rough. Almost like I when you retard a distributed distributor on an engine. Then last night on the way home on the highway, sometimes when I lightly accelerate the car seems to stumble and it has stumbled once when idling. Can someone point me in the right direction, is it the opti, coil, injectors or a bad sensor?? 
No codes, except a 28 Quad Driver, but I been messing with that for over a year.
TIA
No codes, except a 28 Quad Driver, but I been messing with that for over a year.
TIA
Last edited by Randy93; May 11, 2006 at 12:35 PM.
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
You have some classic opti symptoms. I pretty much had the same on my 11 year old opti. It would stumble at idle, kick and buck on accelleration, but not all the time. Ran good again when I changed it. But before I did that I went thru all the moves and checked every sensor and everything under the hood. Even changed the coil. Don't here about many being bad.
The ICM is an item that does go bad and should be considered. They can be checked but replacement is best. Sounds like your heading for an opti, but do the basic checks first. Fuel pressure and all. Good luck. Charge on
The ICM is an item that does go bad and should be considered. They can be checked but replacement is best. Sounds like your heading for an opti, but do the basic checks first. Fuel pressure and all. Good luck. Charge on
Burning Brakes
Joined: Feb 1999
Posts: 1,157
Likes: 3
From: Encino CA
Originally Posted by pcolt94
You have some classic opti symptoms. I pretty much had the same on my 11 year old opti. It would stumble at idle, kick and buck on accelleration, but not all the time. Ran good again when I changed it. But before I did that I went thru all the moves and checked every sensor and everything under the hood. Even changed the coil. Don't here about many being bad.
The ICM is an item that does go bad and should be considered. They can be checked but replacement is best. Sounds like your heading for an opti, but do the basic checks first. Fuel pressure and all. Good luck. Charge on
The ICM is an item that does go bad and should be considered. They can be checked but replacement is best. Sounds like your heading for an opti, but do the basic checks first. Fuel pressure and all. Good luck. Charge on
Racer
Joined: Jan 2005
Posts: 476
Likes: 0
From: Tucson, AZ. L98-85 AUTO COUPE: 120k MILES: daily driver. SOUND OFF IF YOU'VE BEEN THERE. Ex-Jumpin' Junky-82nd Airborne-2/505 PIR: 1st ID-1/16th Inf: Recon Marine Retread. GOD BLESS GRUNTS.
the question is: how long after the tranny rebuild did the symptoms appear. you must tell the doctors all the info. you'll only get so many replies, and you want to get the problem solved.
list anything done prior to the problem and a time frame.
just trying to help, not spank.
list anything done prior to the problem and a time frame.
just trying to help, not spank.
Thread Starter
Melting Slicks
Joined: Feb 2005
Posts: 2,135
Likes: 0
From: Sebastian Florida
St. Jude Donor '06
It started 2 days after I got the car back. I am not sure it is the opti, because when the car is cold it runs pretty good. It only starts when it gets up to temp.
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
I know people jump on the opti, but you could be describing my symptoms on my car as I had them. Like I said you still have to go thru the moves of checking other things. It's unlikely you have a open temp sensor, not many go bad. If it opened you wouldn't believe how bad the car will run, it will go very rich. As temp goes up, resistance goes down and is a big driver in the A/F ratio. You can check it, if I remember it's about 3000 ohms at 70*F. 
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Le Mans Master
Joined: May 2005
Posts: 7,301
Likes: 2,222
From: Central Maryland
Originally Posted by Randy93
It started 2 days after I got the car back. I am not sure it is the opti, because when the car is cold it runs pretty good. It only starts when it gets up to temp.
I'd suggest you first verify fuel pressure while it's misbehaving.
Be well,
SJW
Racer
Joined: Nov 2000
Posts: 351
Likes: 0
From: Allen TX
I'll have to agree with Carpenter on this one...I had a bad water temp sensor (on the front of the water pump) and after the car got to 215 or so (Dallas summers 
) it would it run like crap, bucking on acceleration and idling bad. On the digital display, my coolant temp would jump all over the place, from 215 to 97 to 160 to whatever, every second or so. Because of that, I knew it was some kind on sensor.
Anyone fill me in on what an ICM is :o Seems like lately everyone is talking about a bad ICM and I don't even know what it is
) it would it run like crap, bucking on acceleration and idling bad. On the digital display, my coolant temp would jump all over the place, from 215 to 97 to 160 to whatever, every second or so. Because of that, I knew it was some kind on sensor.Anyone fill me in on what an ICM is :o Seems like lately everyone is talking about a bad ICM and I don't even know what it is
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
The ICM is the ignition control module. It is the unit that mounts on top of the coil against the block. It is held on with two screws and has one 4 wire connector on it. It takes the spark drive pulse and amplifies it so that the coil can be driven. The pulse gets amplified from about 5 to 40 volts. 
The coolant sensor on the pump drives the PCM for fuel management. Another temp sensor on the left side of the block drives the temperature gauge and read out. I don’t understand why your temp gauge would jump around?
The coolant sensor on the pump drives the PCM for fuel management. Another temp sensor on the left side of the block drives the temperature gauge and read out. I don’t understand why your temp gauge would jump around?
Racer
Joined: Nov 2000
Posts: 351
Likes: 0
From: Allen TX
Thanks for the heads up on the ICM. When the car was running BAD, that digital temp readout was like a random number generator...I was watching it and I was thinking, "this can't be good". I think the PCM was confused because it couldn't tell what the temp was so it was trying to adjust everything. Anyways, after I replaced that sensor, all was good.
Le Mans Master
Joined: May 2005
Posts: 7,301
Likes: 2,222
From: Central Maryland
Originally Posted by pcolt94
The ICM is the ignition control module. It is the unit that mounts on top of the coil against the block. It is held on with two screws and has one 4 wire connector on it. It takes the spark drive pulse and amplifies it so that the coil can be driven. The pulse gets amplified from about 5 to 40 volts.
The coolant sensor on the pump drives the PCM for fuel management. Another temp sensor on the left side of the block drives the temperature gauge and read out. I don’t understand why your temp gauge would jump around?
The coolant sensor on the pump drives the PCM for fuel management. Another temp sensor on the left side of the block drives the temperature gauge and read out. I don’t understand why your temp gauge would jump around?
Be well,
SJW
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
Your right on the temp sensors. just a slight memory laps. After you said it I realized I knew it but went off base that time. Won't forget next time. Anyway its an easy thing to check, then you can move on if need be. 
Thanx
Thread Starter
Melting Slicks
Joined: Feb 2005
Posts: 2,135
Likes: 0
From: Sebastian Florida
St. Jude Donor '06
Update, it is starting to run rough all the time. When I start the car(cold or hot) and I walk to the rear, I can smell gas from the exhaust. I got a new fuel filter, just with other problems I haven't put it on yet. I am doing this because I have 40k miles since the last one, noot throwing parts at it. I have a couple of questions.
1) what should the OHMS value be on injectors?
2) How do you use a noid?
3) Used Seafoam today and barely smoked. Put it through the booster line at idle. Put 2/3rd's in the hose and rest in tank. Now the car idles worse, did I do something wrong?
Put it in slowly like the can said at idle.
TIA
1) what should the OHMS value be on injectors?
2) How do you use a noid?
3) Used Seafoam today and barely smoked. Put it through the booster line at idle. Put 2/3rd's in the hose and rest in tank. Now the car idles worse, did I do something wrong?
Put it in slowly like the can said at idle.
TIA