Hello friends, hope you can help me with this problem that it is bottering me now....

I have a '07 Pontiac G5 with 2.4 engine, recently started to develop some problems under acceleration... Example, starting from a stop at normal acceleration the engine starts jerking like if you were lifting the foot of the accelerator under acceleration... the problem started with a little feeling of jerking but as time goes the problem is getting worst and it is jerking more often and stronger than when started...

The car only has 6,000 mi since last tune up on the dealership were it was changed all filters including full (22300mi total on the car).

I went to the dealership to see what was wrong with the car and... their solution was reseting the computer...

And well funny but reseting the computer the problem seems to disappear but as soon as it finishes the learning mode it starts again with the problem.

I already verified everything on the engine, no air leaks, no oil leaks, the throtle body is "clean" and doesn't have debris.

So, what do you think would be the problem?... I was thinking on dirty injectors but, doen't sound logic considering that has new fuel filter and the behavior when reseting the computer

MAF maybe?

PS... It doen't throw MIL code


Thanks in advance

 

clean your maf

or

let me gues you have an auto?

if so you're bcm is probably going on the fritz

 

MAF related issue in my opinion.

 

It has manual transmission

 

Remove your throttle body and clean it out

 

water in the fuel will do the same thing it happened to me just get dry gas injector cleaner and fill your tank at a place you trust you should be fine

 

Throttle body completely clean and also using an injector cleaner but no results... same conditions...

Also forgot to mention that it feel like with lack of power....

 

have you gotten any check engines or other lights on the DIC?

 

Not at this moment... haven't had any MIL on the DIC....

Well... another symptom, when stop, running engine, AC turned off, the RPMs goes, without touching the pedal, to 1000-1200 RPMs and doesn't stay stable... sometimes goes below the 750 but can't stay stable.

 

if your idle is jumping definitely clean your maf

 

Well... after a week in the dealership I can say that worth the time in it... I received the car, and after 3 weeks of using it it feels great... I must say that comparing it now I think that my problem had long time, the car accelerates really nice and recovered some MPG... I have tested it for about 1000 mi with no problem and last week drove on highway for about 250 miles reaching and maintaining 110mi/hr with no problem... befire the adjustment I couldn't reach it.

The dealership cleaned the MAF and adjusted the throttle body, it was part of the problem. But... knowing the dealership, I had to produce a MIL code in order to accept it without an appointment so, I disconnected the MAF for a while and then took it to the dealership.

Good service after all... and, because my warranty was about 2 days left I asked them to check a noise in the passenger side front wheel... I turned into a broken shock absorver....so they changed both front under warranty.