SNKPWR

I found lots of info saying check the MAF signal, clean the maf, replace the maf, could be leaks at t/b or egr...and symptoms of bucking and stalling, which sounds similar to my issue, but none have been exactly the same...

2002 gpgt, dhp 1.0 PCM, stock airbox removed and open s&b filter on the end of the stock inlet tube...this started shortly after i changed the filter from stock airbox to open filter, but does not go away w/ stock setup back in place...

when coming to a stop about 3 out of 5 times, the rpm's will start fluctuating, car jerking, and there is a jet-plane WHOOSH emanating from the intake/throttle body (actually you hear it from the filter area, b/c that is what is open)...i mean it is LOUD....then after a couple neutral revs, or some acceleration, the rpm's will go right back to normal and it runs fine for a while...

checked the code w/ a tech II and got P0102, read on here, and cleaned my MAF w/ sensor cleaner...ran decent for a day or two then went right back to doing it...

now i just read on here tonight something that i missed before, i tried unplugging the MAF while the rpm's were going bananas, but haven't tried disconnecting it w/ the ignition off as i have read on here...does that make a difference?

i was also wondering if the Tech II will datalog sensors, so i can maybe capture the funky activity and narrow it down to a particular sensor/circuit...

Thanks in advance for any help!!

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-2002 Grand Prix GT Black

03impala9c1

the tech II will in doubt capture sensor readings, as most scanners do... it is a factory pre-oiled i assume and i know K&N filters have an issue relating to MAF issues... thats what i would check first... and more than likely if you disconnect the maf while the car is off the vehicle will fail to start

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BNaylor

That is incorrect. Disconnecting the MAF sensor to see if driveability returns is part of proper troubleshooting and even contained in the GM FSM. It will not prevent the vehicle from starting. All the PCM module will do is see the lack of a MAF sensor input signal and then uses pre-programmed defaults and other sensors.

The MAF should be disconnected while the ignition to off. Then start the car. The idle will be erratic until the engine warms up sufficiently. If driveability does not return then the MAF is not the issue.

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03impala9c1

odd because thats what my 97 aurora did...

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SNKPWR

UPDATE: 4-14-08

took the Tech II at work and hooked it up, checked engine sensors while running, and when this problem occurs the IAC "counts" shoot up from ~75 to ~250, MAP pressure goes up from ~30 to ~65...also during this the MAF reads 0 Hz, but i was curious if just a bad MAF could cause all of this?

i guess i'll order a new MAF and see if that corrects the problem...

on a slightly different topic...w/ the DHP 1.0 PCM, i have to read PCM functions under a 1999 W code, and for trans and other functions i use the correct-for-the-vehicle 2002 W code...i think i remember this being an issue when i had the CPS relearned after installing the DHP...

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-2002 Grand Prix GT Black

SNKPWR

got the new MAF installed this morning, reset codes...everything seems to be working OK...

i'm thinking that the PCM saw a sudden loss in maff signal, thought NO air was coming through, immediately opened the IAC...when that caused the idle RPM's to go up, the PCM de-fueled causing the stumble and occasional stall...does this make sense to anyone?

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-2002 Grand Prix GT Black