02 blazer hard to start and misfiring
 

hi everyone. im new to this forum. i have an 02 blazer 4.3l and it has a problem that seems to be getting worse. a few months ago it started to get a rough idle and hesitate while accelerating. after a while i started getting a flashing check engine light which i think means i could be damaging the cat so i quit driving it for a few weeks. i went to start it and it had to crank for at least a minute before it started. when it did, it sounded like it was only running on 1 or 2 cylinders, then they all slowly started firing with just a miss here and there. after i shut it off it was able to start right up again easily. if i let sit for more than a day its hard to start again and has to crank for a long time. i replaced the ignition coil and no difference. i looked at the service records and spark plugs were checked recently and plug wires are almost new. i think it may be fuel related but not sure where to start.i still need to do a fuel pressure test. any ideas would be much appreciated.

Start with the fuel pressure and leak down test. Post back your results

hello again, i finally got back to working on my blazer.i did the leakdown test and everything seems fine. when i turn the key on it goes up to 60 pounds, when running it stays between 55 and 60 and when i shut the key off it stays at 60 for at least a half hour. unhooked it after that. any other ideas?

any other sel codes?

i havnt run the codes yet

i have to drive quite a ways to get to autozone, unless napa does that but i doubt it

Without codes you would just be throwing random parts at the problem.

well i decided to try changing the sparg plugs just to see what would happen and it completely fixed the problem. check engine light went away, ran perfect, started fine. ive been driving it for a couple weeks now and its starting to miss again. still starts fine and no engine light but i think there is something causing the plugs to foul. any ideas?

anybody?

Did you use AC Delco plugs? From what I've learned on this forum this engine apparently is very touchy and you have to use AC Delco secondary ignition parts.