HELP! Running Like Crap!

[Wess]

I posted this to the mailing list so please excuse me if this sounds familiar.

I changed the rear bank coils, plugs all around, and added some phenolic spacers a little over a week ago. Prior to doing this, I had a slight miss that I determined was one of the rear four coils. After replacing everything and firing back up, the car ran great. In fact, it had been running better than it had in a long time. This morning on the way to work I felt a slight miss and thought one of the front four coils was starting to give me problems, it wasn’t too bad so I continued on to work. When it came time to go home I had much more severe situation, the car was sputtering and just plain running like a$$. The CEL was flashing when the engine was under throttle, and then eventually stuck on. Exhaust smelled of a way rich condition too. I hooked up the scanner and pulled a P0308, which is a cylinder 3 misfire. I also checked all my vacuum connections thinking something came loose, everything looked ok. WTF could be causing this? I appreciate your advice, this is my daily driver and I’m really up the creek here. Thanks.

 

[Wess]

Disregard this post. Problem was solved. Thanks for reading.

 

[SHOGrabber]

Don't leave us like that!
What was it?

 

[Wess]

Sorry about that. As it turns out, I had another bad coil. Rather than slowly failing over time, this one just flat out quit. I couldn't believe how bad the car ran. I never suspected it, becuse I misinterpreted the code for some reason. P0308 is cylinder 8, not 3. I will be rolling with the remaining coils I have in the trunk.

 

[SHOGrabber]

I think I have one slowly failing in my wifes 98 SHO.
We just got it for her about 2 weeks ago and bought it with a misfire in #3 cylinder. I replaced it and it run good on my test drive.
She tells me a few days later that it didn't feel right when in gear sitting a light. I drive it and it runs good going down the road. But at a light it will miss yet then it will run smooth and then miss some more.
Do they go bad like that?

 

[SHOMEX]

Most of the time yes! they fail little by little and some times will fail at once but thats not likely to happen

 

[SHOGrabber]

 

[Wess]

I think I have one slowly failing in my wifes 98 SHO.
We just got it for her about 2 weeks ago and bought it with a misfire in #3 cylinder. I replaced it and it run good on my test drive.
She tells me a few days later that it didn't feel right when in gear sitting a light. I drive it and it runs good going down the road. But at a light it will miss yet then it will run smooth and then miss some more.
Do they go bad like that?

That's what threw me for a curve last night. Before I changed the back four, I had a subtle miss at idle, give her some throttle and it ran smooth. After I swapped them out the car ran great. Then yesterday I noticed a miss again at idle on the way to work. No biggie, kept driving. The trip home was a different matter. The number 8 coil just quit all at once, had me thinking it something entirely different.

 

[SHOspazz92]

We had one go out in the 96, It just quit. Car ran like absolute crap. Oddly enough, It started working again on the way to the mechanic's for about 30 seconds, The car ran awsome. However as soon we pulled in there...It quit again

-Sam