Thread: Terrible stuttering/stalling problems

I have a 2001 Grand Prix GTP. It has about 100,000 miles on it, bought it at 92,000 for about six grand, it was in really good condition, and it ran great, and has ever since I bought it.

I recently returned from a trip from St. Louis back to Chicago, and I had my oil changed at Jiffy Lube. Car was fine, hardly drove it in the next two days, then I went and got gas at a BP station, premium like always, but in retrospect, I realized they were filling the underground tanks.

About 2 minutes after leaving the station, she started stuttering, and I'm assuming it was some sort of misfiery thing. The SEL came on, and I managed to get the car home.

I had thought that maybe I had gotten water in the fuel system, so I let her sit, and started it up, and it promptly stalled out from idle. I started it up again, it ran rough for a while, then ran ok enough for me to run to Autozone to pick up a bottle of Heet, thinking that would fix the water problem. I also had them pull the SEL code, and it was something about the MAF sensor. Lean MAF something or other. So I also picked up a bottle of MAF cleaner and the Torx bits.

The Heet did little to nothing, so I pulled the MAF and sprayed it down. I promptly replaced it, where the car died on me. I got it running and it was horribly stuttery and jerky. I had assumed that if it was the MAF sensor, cleaning it would fix it... So I pulled the connector, and lo and behold, the car runs rough at idle, but she's fine other than that.

Sorry for the horribly long post, but should I just bite it and buy another MAF sensor to replace it? And if so, aftermarket, or OEM? Does it matter even?

If you have a lean code then typically those are form vacume leaks. I have never had a vacume leak cause a stalling issue on one of these cars, But it is possible.


Verify that code for us.

Originally Posted by TDCRacing

If you have a lean code then typically those are form vacume leaks. I have never had a vacume leak cause a stalling issue on one of these cars, But it is possible.


Verify that code for us.

But then why would disconnecting the MAF sensor help? I'll have to go and find out what that code was for sure.

I'm not sure. All that happens in the PCM when the MAF is unplugged is the PCM resorts to the VE table. Which is pretty close to the MAF as far as fueling goes.


If your thinking that the MAF is bad then that's not the case. I have never heard of the MAF going bad and throwing a lean code. Like I said the most common symptom of a lean condition code is a vacume leak on these cars.



Although I guess anything is possbile.

Originally Posted by TDCRacing

I'm not sure. All that happens in the PCM when the MAF is unplugged is the PCM resorts to the VE table. Which is pretty close to the MAF as far as fueling goes.


If your thinking that the MAF is bad then that's not the case. I have never heard of the MAF going bad and throwing a lean code. Like I said the most common symptom of a lean condition code is a vacume leak on these cars.



Although I guess anything is possbile.

How do I go about hunting down a vacuum leak? I know a fair bit about these cars, but everything I know, I've learned in the past month. Am I better off taking it to a mechanic and telling him that's what I believe it is?

Look first. Look by the Evap canister (little round black thing near the middle of the firewall. Should have a vacume line running to it. Make sure they are all the way pushed on. Check your spark plug wires also. If you can get the car to run spray the lines down with carb cleaner. IF you hear the idle raise you've found your leak. It's either going to be a hose that's dry rotted or a hose that is not connected properly.

Code was P0102 - Mass or Volume Air Flow Circuit Low Input, I'm almost certain.

That is a Bad MAF.

Originally Posted by TDCRacing

That is a Bad MAF.

Since it runs perfectly with it disconnected, just slightly off at idle, should I just replace it then? Cleaning it did nothing, so I'm assuming it's more internal that just dirty.

usually if the maf is giving you fits, cleaning wont help. they go bad. replace it. the only thing that sucks is its expensive like 194 bucks.

If your looking for used, Get one from morad parts company like stated above.

Originally Posted by TDCRacing

If your looking for used, Get one from morad parts company like stated above.

Emailed Ed about the MAF sensor, and he says they don't have any, and he's had plenty of trouble keeping them in. Any other places I could turn? Not a whole lot of luck on Ebay..

Originally Posted by pontiackid

Local salvage yard chain. But, make sure they have a money back policy in the event that theres doens't work either... or give them your old one :P

On a side note w/o the MAF your MPG will drop a little and she will run a little hard. Though from experience if the motor is "shaking" hard you definatly want to check the plug wires and plugs.

Yeah. Had brakes done a bit ago, and the mechanic noted that I could use new wires and plugs. Though he was horrifyingly insistent that I stick to AC Delco everything..