“…it would be better to change all 4 of them, something along the lines of since I’m paying for labor etc”. Is that necessary?"
There is almost no labor involved:
I’d get the new plugs and see how it runs. If there’s still a problem, you could put new coils in yourself.
Misfire is the serious problem because it can destroy expensive exhaust system (smog control) parts. After those are finished, the engine is next in line for damage.
Well final update, I’m paying for new spark plugs and new coils and man did it burn a hole in my pocket. Repairs cost me about a grand. Not sure if this is a fair price though but I’ve zero knowledge on this
some service engine soon lights come on after so many miles automatically whether there are problems or not., my cougar had such a light. I have a bad feeling that the op payed a grand when his only problem was an aic valve needed cleaning or some other simple problem unrelated to his light.
@wesw, the code came back P0303. Nothing to do with the AIC or IAC.
oops, missed that
It was checked by mechanic and showing error in EVAP, he told me that gas cap has to be replaced.
Please advice