My tC began having a rough idle a couple of days ago. I replaced the spark plugs and it helped some. It only seems to have the rough idle at a stop or crawl. However, when you push on the accelerator, the engine evens out and runs just fine. I pretty sure there's a miss fire because I can smell gas in the exhaust. There's no backfire though. I'm thinking that I've got a bad coil, or two. The two and three cylinder spark plugs that I took out were both fouled.

I've tried researching for bad coils on here but, it's hard to find good info. I guess what I'm asking for is some sort of verification that this could be the problem (bad coils). I haven't taken the spark plugs back out yet because I've got a strut bar on and I have to be at work early.

Has anyone else been in this situation?

 

bump

 

That sucks man, my 05 xB had the same problem with rough low idle, but when i started driving it, it went away, took the car to a local mechanic, turns out the cylinder head had mishapen. i had to buy a salvaged engine from a wreck, cause it was more to machine the head, good luck to you

 

you dont happen to have a cold air intake installed do you? this was happening to me and i figured out that my rubber gasket that goes around the fender moved out of place causing the intake tube to vibrate against the inside of the fender where the tube passes through.

just a thought.