Is it common for the 2001 Chevy Trailblazer to go through sparkplugs. Last year we had the timing censor replaced. 2 months later spark plugs again. Less than 3 months later plugs again, Now here we are and the blazer feels like it is running on half of it cylenders. It is really bad in the morning and early afternoon hours, however for whatever reason in the later afternoon hours it runs better. We had it put on a computer at a auto parts store and they said its missing on #3 We took it back to the garage that put the timing censor in and they said it is rapidly jumping all over giving codes of missing on all cylenders especially when the a/c is on but not giving an acurate read of what is wrong. We cannot seem to find out what is wrong with this vehicle, when you have the a/c on it run really bad and acts like it is gonna stall out. It drops down to 200-300 rpm and then jumps back up to 1100 then back to around 600 at an idle with the ac on. Off its not that bad it just feels like its missing and little power at take off. Please someone with information about this vehicle let me know this is very disturbing that it is running like this and no one knows why I do not want to ruin the engine.

 

Have they ever showed you what the old spark plugs looked like? You may want to take it to a different, reputable shop or real service department. One possibility is the dumbasses forgot to do the "crankshaft position system variation learn" procedure after replacing the CKP sensor. Either that or the crankshaft balancer is worn and wobbling around.

 

2001 should be a blazer not a trailblazer


any way the trailblazer uses an Iridium plug if you put in any other kind watch out