my car has been hesitating for some time now. i replaced damn near everything and still had the problem. i sorta have it narrowed down to the MAF. with it plugged in the car hesitates at part throttle, WOT is perfect. i unplugged it and drove the car for a lil while and it ran like a dream. only thing is it did NOT pop a code. plugged it back in and car ran like ****. i swapped it out with a known good MAF and same thing happened. car is tuned by EPP with EFI live. what does this mean? any help is greatly appreciated. thanks!

 

Are you talking about a stock MAF? Also, does your tune block codes like P101? You really ought to set a code by unplugging while running, if not its probably being blocked by your tune. Also did you check all the plumbing in front of your blower? A leak before or after (blow-thru) would a cause similar situation.
When you say you replaced with a known good MAF and same thing happened, do you mean it hesitated or ran like a dream? Let us know.

 

yes it's the stock MAF. i don't believe my tune blocks any codes. plumbing is ok. swapped it out with another MAF and car ran like **** still. thanks for replying!

 

I'll be watching this thread. I suspect my MAF is causing my rough running at low speed.

 

i know my vehicle is not FI but i had a low speed low rpm dead spot until i cleaned my maf and swapped the ported MAf ends off of it, replaced with stock maf ends with screen still on. it's possible that the sensor itself is dirty not alowing it to give a true reading.

 

i used electrical cleaner on both MAF's and still no change. the MAF's are stock with the screens still in both. are not ported either. someone else was saying he had this problem and it wasnt the maf it was the tune. his maf and map sensors were fighting each other at part throttle. anyone know anything about this?