3800Pro Forums banner

1 - 7 of 7 Posts

·
Registered
Joined
·
9 Posts
Discussion Starter #1
Alright, Im new here and this is my second post. Ive got a problem that started yesterday. Ive had this problem with my camaro (2000) where when I give it some gas...not flooring it but firm enough to get some speed. When I do this it seems to jump back and forth between 3rd and 4th gear usually (its automatic) anyway it bounces and jumps and what I usually do it completely let off the gas and then floor it and level down the gas again to where I wanted it. This problem has lead me to believe the throttle position sensor is bad...and I have another post about that...I just thought I would mention this as it could be connected. So anyway yesterday on my way home it seemed to be alot worse so I tried to floor it and level it out and then bam! my service engine soon light blinks and come up. When I got home I read the code and it was telling me that I had a misfire in cylinder #4. Ive check the spark plug wire with a multimeter on ohms. I pulled the #4 cylinder spark plug out...didnt look too bad but i scuffed it up with a piece of sandpaper and closed the gap a little, also sprayed some carb cleaner on it, let it dry and put it back in. I havent driven it yet but I will soon, I plan on clearing the code first. I figure if I get the code again Ill swap a coil pack around and see if the misfire problems follows. If that doesnt work where should I look next? Could it be that this misfire was my "TPS" issue and the code didnt come up untill recently??? Thanks guys I appreciate it alot
 

·
Registered
Joined
·
187 Posts
If I were you I would look into the ICM (Ignition Control Module) ASAP. It's the electronic module that your 3 coils sit on. If you are going to swap coils around you may as well at least pull it off and have the parts store test it - not necessarily a definitive answer/test but it will be a good starting point anyway. Had a similar issue recently with the Firebird that a new ICM corrected, was the #5 missing in my case.

One thing I notice on my Firebird is that the weather stripping at the base of the windshield that is suppose to keep water out of the engine bay is very loosely fitted. So when water runs down the windshield a lot of it caught and diverted away but a good portion gets through and leaks all over the 2-5 coil, ICM, and the #5 and #6 injectors. Might just want to check that anyway while you're in there.
 

·
Registered
Joined
·
9 Posts
Discussion Starter #3
Man you said ICM, all I saw was $$$ haha, anyway. Alright I can go have it checked out. Would they test it at Autozone??? Or Oreilys or maybe Advanced? If they do test things like that I had no idea, I thought the extent of the things they tested were starters batterys and alternators. But if thats where I need to go Ill jump on it. I assume I would need to take it off and take it to them to test it. I dont really want to drive it much with this problem. Any idea what an ICM costs? It seems like when you have 1 mechanical problem alot follow. A few days ago I noticed my crotch rocket is leaking gas from the rear carb...yay. Anyway thanks for the quick reply man!
 

·
Registered
Joined
·
9 Posts
Discussion Starter #4
By the way, I just googled up the ICM and well theres alot of varying prices on it...but I mean there doesnt really look like theres much that could go wrong with it other than maybe a busted lead or something...I dont know if theres something inside of it like a computer board or something. I mean if theres something cracked inside it could I just solder it back togather? Ive got a multimeter to check out voltages if you know a specific number I should be looking for
 

·
Registered
Joined
·
9 Posts
Discussion Starter #5
Man! Im glad you mentioned the ICM! I had a little time today to check it out. So I pulled the coil packs off and looked at the ICM, the coil pack position for #4...the terminals looked so calcium built up I figuered that had to be the issue...or at least a great place to start. I pulled the ICM...took a while because I didnt realise there was a bolt in the end of the connector. Anyway I pulled the ICM and cleaned up all the terminals with some sandpaper. It was really caked up bad and took a long time to clean up. I shot some carb cleaner over all the terminals, and shot some into the coil pack slot holes, icm connector both male and female ends. I let everything dry out real good, hooked it all back up. Then I cleared the code and took it out for a test drive. Jesus man! Its never ran better! I was able to floor it and it ran perfect, it even shifted through all the gears smoothly the way it should have, before I thought there was a problem with the TPS also but seems that I must have just been running on 5 cylinders.
My only question now is...this problem may have been going on for a long time now. If that #4 cylinder hasnt been firing for such a long time, what kind of damage could that have caused? I just want to know before hand. Thanks buddy I really appreciate it alot!
 

·
Registered
Joined
·
187 Posts
Glad you got it fixed. That's another reason I mentioned the weather stripping at the base of the windshield (where the hood meets at the top). The only thing that compresses that stripping is the hood and it's not usually a tight fit after after several years. This allows all the water flowing down the windshield to pour over the 2-5 coil/ICM and some of the injectors. You may want to consider adding a bead of silicon to the base of the stripping and reapplying it for the future.

I had a similar issue recently where I had a stumble under light throttle and a general random miss on cylinder #5. After some trouble shooting I narrowed it down to ignition and after seeing no difference swapping coils I tried a spare ICM I had laying around which corrected the issue instantly. Your symptoms sounded identical. May not have been an internal problem with your ICM (There is a computer module inside) but corroded leads will certainly cause your symptoms as you've found out. You can also have it tested someplace such as AutoZone, they do test multiple types of ICMs as well.

You could have also bought new seals for your ICM where the coils mount (Those orange seals around the ICM leads) for better insulation or used some dielectric grease on them but if you add some silicone to the weather stripping above that area you'll probably OK in the future.

Running with a misfire for a short while probably won't do a whole lot of damage. First thing that comes to mind is fouling out the catalytic converter with unburnt fuel but if the car is running OK and no cat codes or O2 codes are present I wouldn't worry about that yet.
 

·
Registered
Joined
·
9 Posts
Discussion Starter #7
Im glad i got it fixed too man, i really appreciate the advice! Im really glad i have a code reader too. Ill probally end up laying down a good bead of sealant too, i bet that will help alot. When i got this camaro there were so many things wrong with it. Slowly but surely im getting things fixed. And ive got alot done on it so far. I do what i can on my own and try to only ask for help when i really need it. I did happen to check out those seals when i had the icm off and they looked to be in good condition, really good actually. I also noticed that the center and rear coil packs look like they were replaced. I have the front one that has the 3 and 6 o. It but the other 2 are blank. I got this car from my sister, she said a mechanic told her the cat needs to be changed so i guess ill be doing that soon anyway, once again i appreciate the help man!
 
1 - 7 of 7 Posts
Top