Guys, first off thanks to the knowledgable folks that post to this forum like Ian and Doc and others- ya'll helped me before and now I've got a new gremlin.
Truck was running fine, started it up this morn, moved it forward about 10 feet into the garage, and proceeded to swap out a right front stereo speaker.
Finished the installation, started the truck to hear the stereo, and damned if I don't have the 'check engine soon' light on. Light is on steady until I drive it a little and then the light starts blinking. Truck was running rough, like I was down one cylinder (5.3 L v8). Ran down to autozone, plugged in their diagnostic machine, and got back a report of a misfire on cylinder 3 (actual error was a 'POS-303' or something like that then the machine flashed 'misfire cylinder 3' - saw it with my own eyes so it's not the technician messing with me). I've got 52k miles, just recently refreshed my K&N (bought before reading this newsgroup's opinion), last fuel filter at 30K, Mobil 1 changed religiously, premium gas only, etc. Only thing I haven't done is the PCV valve and the sparkplugs.
I'm trying to think what would cause a misfire on 1 cylinder. Either no gas or no spark or a combo of the two. I made sure the wiring harness for the injector and plugs were tight, wire looks good. Haven't yanked the plug itself yet as I'm waiting for the head to cool. I went ahead and bought 8 new plugs and hope to God this fixes the misfire. Gapping them to .060 and will install in about 30 minutes...
The sales rep sold me Delco 41-932's, which from my silverado manual are recommended for the v6 only with 41-952's for the V8. I called back autozone telling them they sold me the wrong plugs and they said the 932s are the regular platinum while the 952's are the double platinum and that the 932's are fine with my truck.
So, several questions-- if plugs don't fix my misfire, what else can I check? Secondly, are 932's ok or should I really find 952's? Lastly, if the condition is corrected with plugs, will the warning light go away or do I have to reset it somehow? Thanks for the help everyone.
Chris