[ap0001]

99 Silverado 4x4 - 5.3L - Engine code calling misfire. Discussed with previous owners mechanic and he said they replaced fuel injector for misfiring cylinder - then problem jumped to another cylinder! Previous owner installed Bosch Platinum +4 plugs. I'm starting with new plugs, then wires, then coil packs , then injectors, and so on. Any suggestions?
FYI - Service engine light is normally constant. Every once in a while, service engine light will not come on when I start the truck. After about 10 minutes of driving or so, it will come back on and I can detect a slight hesitation in the engine performance. Problem seems intermittent. Thank you for any input.

[AirWreck09]

If when you pull the plugs out and their covered in oil or covered in raw gas you ll have to change the plugs out but since you did that it should start running fine. I would run the truck for a while then pull the new plugs out and see if they are doing the same thing over again, your best bet would to change the plugs wires and i would also run some fuel injector cleaner through the system and see if that clears anything up.

[AirWreck09]

Oh and one more thing i forgot to mention, try a compression test you should be running a compression between 100 and 120 if its anything lower than 100 you might have a burnt valve problem but i doubt that would be your prblem.