running rough, please help
So I have a running rough problem
Car kind of "surges" for a few seconds like its loading up, then instantly get a big increase in power. Only way I can describe it is it feels like its starving for fuel for a few seconds then gets a big kick in the ***.
-happens under normal acceleration (25-50% throttle), never at WOT
-usually starts around 1800-2400 RPM
-has no MIL/SES light, but pcm was messed with before I got the car so they may have disabled the light
I have done the following after having the problem and didn't notice any change
-port and polish TB (super clean and not sticking)
-new plugs and wires
-Seafoam through crankcase, vacuum, and gas tank
-replaced both upstream o2s (needed done anyway)
-replaced fuel filter (needed done anyway)
As i said, I now someone has messed around in the pcm before so I was thinking it might be something they did with a "tune". The problem is intermitent but happens more often than not.
Anyone have any insight or advice?
I was thinking possible TPS, but dont want to keep throwing parts at it that arent needed
Last edited by simplysix; Mar 2, 2012 at 12:57 AM.
Thanks again for any help guys and girls!
So I have a running rough problem
Car kind of "surges" for a few seconds like its loading up, then instantly get a big increase in power. Only way I can describe it is it feels like its starving for fuel for a few seconds then gets a big kick in the ***.
-happens under normal acceleration (25-50% throttle), never at WOT
-usually starts around 1800-2400 RPM
-has no MIL/SES light, but pcm was messed with before I got the car so they may have disabled the light
I have done the following after having the problem and didn't notice any change
-port and polish TB (super clean and not sticking)
-new plugs and wires.
-Seafoam through crankcase, vacuum, and gas tank
-replaced both upstream o2s (needed done anyway)
-replaced fuel filter (needed done anyway)
As i said, I now someone has messed around in the pcm before so I was thinking it might be something they did with a "tune". The problem is intermitent but happens more often than not.
Anyone have any insight or advice?
I was thinking possible TPS, but dont want to keep throwing parts at it that arent needed
I replaced the maf and didnt notice any change, So I went to my dynotune appt today and he found the problem. the maf/02 fuse was blown. Got it tuned and its running like a champ!
Last edited by simplysix; Mar 6, 2012 at 08:55 AM.


