Grandprix Chugging after startup...dies

**ajc549FF** · 02-04-2013

Hey all.

So my 98 GTP was running perfectly fine this morning while driving home. Two hours later I used the remote started the car and it sounded like it had a cam so I cut it and took a look under the hood just to make sure everything was as it should be.

I started it back up a minute later and it ran fine so I got in the car and reversed it out of the driveway and the gtp began really chugging, i put it in drive and tried to get it back in the driveway and it wouldn't even move then began to move an inch then the engine wanted to die (I was giving a good amount of throttle) Got it back in the drive and tried again, same thing happened.

What do you think? Tune up last year along with new fuel filter last year.

Thanks.

**FordMan77** · 02-04-2013

Is the CEL on? Try disconnecting the MAF and see if it runs better. It will want to idle badly for a bit so keep some throttle on it and it should stay running. If this helps then you could have a bad MAF. Oh, and don't drive around w/o the MAF connected more than you have to, and def. stay out of boost.

**SlowNA06** · 02-04-2013

I'd look into the MAF. Maybe a clog in the air intake somewhere. Or a massive vacuum leak.

**ajc549FF** · 02-05-2013

No the CEL is not on. I unplugged the MAF but no change...

**SlowNA06** · 02-05-2013

No change after unplugging MAF? Jolly good. Sounds like the MAF isn't working.

**ajc549FF** · 02-05-2013

Thats what I'm thinking...I went outside just a half hour ago to start it up with wishful thinking it was fine for about 2 minutes then started acting up again....but I saw the Check engine light on and got my scanner...by that time the engine choked out and I attached the scanner and nothing on the scan and I realized the CEL was off! :/

**SlowNA06** · 02-05-2013

It should still have codes stored.

**BlackGT97** · 02-05-2013

it almost sounds like it is not firing on all the cylinders, like a bad coil pack almost.

**SlowNA06** · 02-05-2013

Originally Posted by BlackGT97

it almost sounds like it is not firing on all the cylinders, like a bad coil pack almost.

That probably wouldn't cause stalling, just breakdancing.

**FordMan77** · 02-05-2013

breakdancing.jpg

Could be a failing ICM. You need to see if you can get those codes read. Would take some of the guesswork out of it.

**ajc549FF** · 02-06-2013

Yeah im going to try using a different reader tomorrow hopefully if i can get my hands on one...maybe could it be the CPS? Literally it starts just fine then after like a half a minute it starts to chug and loap like a cam then stalls out.

**Explicit_Spade** · 02-06-2013

Crank Position Sensor.

Or tune. I made a stock GTP lope hard at idle once via tune.

**ajc549FF** · 02-06-2013

Is there a relearn process for the car with replacing the cps?

**ajc549FF** · 02-07-2013

SO update here!

Messed with it again today I unplugged every sensor separately starting the car with each individual unplugged and no change in how the car was acting. BUT we plugged everything back in and started it up, it wanted to die like it has been, we kept throttle on it for about 20-25 seconds and it got over like this hump and it ran 100% ok! Took it for a drive and everything...we turned it off and let the car cool down started it back up and it started chugging once more so we kept throttle on it for about 20 seconds and it started to run just fine again no issues.

Any ideas?