hey guys just got an account here because i have not really been able to get a clear cut answer as to what my problem would be.

Just for some information to help diagnose the problem.....Recently, my car has begun to chunk out, or hesitate, while i accelerate. Ive noticed this problem only happens after the car has warmed up, and again only happens in a really low range of rpms (1-2.5k). The problem seems worse, or at least the engine seems lacking, when i have the a/c on full blast as well.

Ive already done quite a bit to fix this problem : New NGK plugs (its a 2000 integra gs-r, by the way) new fuel filter, new plug wires, and ive also bought fuel injector cleaner which i will be using soon (a bunch of people have told me it is NOT the injectors, however)

There are so many other possibilities that have come up, just based on what ive read. I know in order to diagnose the problem it has to be specific (for example, a car that hesitates throughout the driving range rather than just on low rpm acceleration probably has a MUCH different problem than mine)

Is it possibly a sensor? clogged Idle air control valve? what else to do with the air mix could it be?

i recently installed a new cat back exhaust and one of the bolts on the pipe connecting to the cat is really not that tight at all, and i believe that is letting a few fumes escape right at the end of the cat. Now im told this could be a problem because a sensor could be reading that as a leak and dumping more fuel into the cylinder. but would this only happen when the car is warmed up? (again, so far ive noticed no hesitating for the first 15-20 miles of driving)

ive also been told it could be the igniton timing- as that can be affected if the idle speed of the engine changes (not really sure if the idle speed has been affected too much since the spark plug change, but don't want to rule it out)

so is it most definitely one of the things ive heard it could be so far? has anyone had this exact problem? is there anything it could be?

All help appreciated (i really want to fix this problem soon!)

Thanks,
Ivan

 

I remembered when my civic had hesitation problems after I swapped out the motor in favor of a gsr. Found out later that we were running b16 injectors. Umm.. try changing the PCV valve?