Start by taking it to an auto parts store and having them check the codes. They will normally do this for free.

Answered by promechanic (expert)
556 answers provided

I've learned that in the 99 Chevy Trk/Sub 5.7 only the AC Delco Spark plugs work. 5yrs ago I changed my spark plugs 3 times in the same month and it ate those spark plugs up. So i shelled out cash for the $8.99 each AC Delco's and problem was fixed. I still have the same spark plugs in my 99 Sub today. I clean them with a battery post wire terminal cleaner and there as good as new.

Answered by passdahotsauce
1 question asked

"I clean them with a battery post wire terminal cleaner and there as good as new. "

That's the wrong thing to do. It leaves metal tracks for spark to jump over. NEVER take a wire brush to a spark plug. You should never need to anyway if the engine is running correctly.

Answered by Wrenchtech (expert)
14,825 answers provided