breaking up after warm

[93/96 f-body]

After my car warms up it starts running rough pops through the exhaust and if i hit the gas it breaks ups bad and hardly wants to do that.It has 129,000 on it.I just purchased it in december.I first found the elbow was ripped badly at the tb.Raplaced that with the trick flow piece.Then after reading 94 formulas forum i replaced the coil and ic module still no luck.I bought the car knowing it had this problem but when i test drove it , it ran fine.I figured it was the opti unit but after reading some of the forums i started with some of the simpler things.The check engine light dosen't come on but one time i did see it flash when i was reving it up which lead me to believe it was the ignition system.I'm guessing its the original opti and older wires.The wires look old.If i let the car run and it warms up to 200 degrees or slightly over thats exactly went it starts doing this.Help i dont want to spend the money and time replacing the opti if its not the problem.I'm go to replace the fuel filter this week also.Thanks for any help love the info on this site.

[N20LT4Bird]

I have the same exact problem with my car. It just started before I put it away for the winter. So, when I pull it out in a couple weeks, I will be dealing with it. I found that spacing the coil and I/C module further away from the head has made the problem better, but it hasnt gone away. This leads me to believe this is the problem area. I replaced it with another IC and coil (used) and the same thing..... My opti is brand new too, but that doesnt mean anything..... I suppose it could be fuel filter issue, but I think I remember replacing mine not too long ago. Joe1320 mentioned the silicone grease between the IC and the bracket could be contibuting to the problem. So, I dont know the answer to your problem......ive got to figure it out too! If I find anything, ill let you know. If you find anything.....let me know, will you?

[raroZ28]

coolant temp sensor, o2 sensor?? How are they?

[Injuneer]

Look at the things that "deteriorate" as they heat up... you already did the IC Module, but "spacing" it as described above might help. The optical sensor in the Opti could become heat sensitive. The wire insulation could lose its dielectric strength as it heats up. A heat soaked IAT sensor could be causing a bit of spark retard that could be loosely interpreted as a miss. Injectors use electric coils to move the internals and they could become sensitive to heat.

Does it run fine on cold start, then after about 3 minutes beging to run poorly, and never recover until the next cold start? Or does it run fine cold, and run fine for a decent period of time after the engine heats up, only starting to run poorly if the coolant temp goes above 200degF?

[93/96 f-body]

breaking up after warm up

I never let it cool back down and trying to run it again so i cant answer your question.I know the past owner put a new water pump and radiator on the car within the past year and after reading some of the forums i was wondering if thats what could have lead to this problem.Meaning a leaking water pump contaminating the opti over time.He claimed he only put about 2,000 miles on it and spent 2,000 in repairs and was tired of it.

[93/96 f-body]

breaking up after warm up

Yes it does run fine until it hit about 200 degrees and then it just goes to pot.But as i said earlier i never let it cool back down and refiring it again.

[FireFinder20]

Does it run fine on cold start, then after about 3 minutes beging to run poorly, and never recover until the next cold start? Or does it run fine cold, and run fine for a decent period of time after the engine heats up, only starting to run poorly if the coolant temp goes above 200degF?

I dunno if he ever solved his problem, but I found this with a search...you've described my problem almost to the letter...I'v emade the mistake of throwing parts at instead of just having someone with a laptop do their magic

[93/96 f-body]

still have the problem

No i never did fix the problem yet.Have you fixed yours and if you did how did you figure it out.Thanks for the help.Funding and fustration halted the prodject.

[FireFinder20]

never fixed mine either...funding and frustration halted mine as well...

i got some O2 sensors yesterday, but i doubt it'll fix the issue...

[DJ Taso]

does it run fine cold, and run fine for a decent period of time after the engine heats up, only starting to run poorly if the coolant temp goes above 200degF?

I have that exact problem, Fred. What do you think it is? The spacing? The IC module?

[93/96 f-body]

update

I replaced my ic module the coil and spaced them about an inch and it still ran the same.I did notice my new coil glowing blue when revving the engine on both sides?I'm selling my second mower so next month I geuss i'll replace the opti, seals and the plugs and wires.I also replaced the thermo stat and installed a tb bypass kit.After that it still did its normal hissy fit but it idles high then start jumping up and down and quits?I had a 96 chevy do the same thing but never qiut and ran fine but just idled up and down like this.It ended up being the EGR value.Wonder if mine is hanging up?

[N20LT4Bird]

I think I finally got mine nailed down. I was driving and the service engine light came on for a second and shut off again. I almost thought that I imagined it......I hooked up the scanner and found a stored code for the bank 2 sensor 1 O2 sensor. I looked at it on the scanner and it was stuck right on .45 volts.....wierd. So, I swapped it out and at the same time installed an MSD blaster coil. I havent had the problem since......so hoopefully either one (or both) fixed it.......

[FireFinder20]

never fixed mine either...funding and frustration halted mine as well...

i got some O2 sensors yesterday, but i doubt it'll fix the issue...

as i thought...didn't do a damned thing


the LT-1 in my squad car runs like a friggin top...wtf can't my T/A?????????

the chopping block is on the horizon

[DJ Taso]

I think I finally got mine nailed down. I was driving and the service engine light came on for a second and shut off again. I almost thought that I imagined it......I hooked up the scanner and found a stored code for the bank 2 sensor 1 O2 sensor. I looked at it on the scanner and it was stuck right on .45 volts.....wierd. So, I swapped it out and at the same time installed an MSD blaster coil. I havent had the problem since......so hoopefully either one (or both) fixed it.......

Interesting. I'm having my plugs and wires redone. I'll tell them to change the O2 sensor while they're in there.

[FireFinder20]

as it turns out, the opti was hosed...

the wheel inside was warped, replaced the opti, now she runs like a champ