Hello Everyone,

I desperately need the help of grand prix veterans. I have a Daytona 500 2000 Grand Prix GTP, I LOVE IT TO DEATH. It stalls randomly, and I shift to park, then start it back up with no symptoms. I receive no check engine codes.

I've recently replaced the fuel pump assembly, which fixed a stalling issue I had about a year ago. It drove fine until I gave it a cleaning at a car wash. It began to miss very badly and threw codes for a misfire on cylinder #3. I had it checked out and apparently the 3rd fuel injector was failing. So I had it replaced, then for a week or so it seemed to drive fine. However, it started randomly shutting off while idling or driving either way. It seems like sometimes on start-up it will be in the 1200 rpm range and fall down to about 900, then it seems like it kind of spikes, I can even touch the gas for about 5 seconds and drop off of it and cause all of the lights to dim, I imagine that might be normal.. but im not sure. I had the timing belts changed yesterday and also the crankshaft position sensor changed because I looked on these forums for possible solutions and it seemed like a good thing to do.

Summary of Issue:
1. Vehicle starts up and sometimes, seems to run rough.
2. Engine seems to randomly shut off while driving with foot on accelerator and while idling in park.

To date I've replaced and had these things done:
BG99K and TB cleaning
Fuel Pump Assembly
Third Fuel Injector replaced
Crankshaft Position sensor replaced
Cleaned MAF sensor, IAC sensor
Checked for Vacuum Leaks
Checked for bad wiring

Things I've been told might work:
PCM Reflashed
Ignition Switch Replacement
Ignition Control Module
Idle Air Control Motor replacement

I know nothing about these cars mechanically, all I know is there is nothing but pure awesome in the thrill of jamming my foot into the floor and letting the wind whip my hair back and forth :O
I just wish I could figure this issue out without dumping more money into things that may not fix my problem. Would any of you gurus have any advice for me? I really really miss my car...

Try this and see if the problem goes away: Fixing your intermittent stalling problem!

You can also try unplugging the MAF sensor, and see if the car runs better.

Oh yea meant to mention that bending that pin, didn't make a difference in the start up, however it did seem to die.. however since its intermittent i cant be sure and i dont want to bend it back again, because I already bent it back.

I tried unplugging the MAF sensor, no difference, even took a peak inside and cleaned the sensor still same performance issues. Good calls though, really appreciate any input

if you've had problems with injectors going bad before, I'd think maybe that's your problem again. when was your fuel filter last changed? You may be getting debris in your injectors or something like that.

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'05 WRX STi - COBB Stage 2|Invidia DP|3" Borla XR-1|Coilovers|Camber Plates|Swaybars|Endlinks|Bushings|Braces|Anti Lift Kit|DBA4000s|SS lines|
Sold: 06 Cobalt SS/SC, 99 GTP 245WHP/326 Ft-lbs, 06 R6

I'm going to be dropping it off on monday at the dealership, I'll have that replaced. I'll see if that makes a difference.

So like 3 weeks later, I was informed that the issue was my ignition control module and my crank position sensor. Oddly, I changed my ICM and I was still seeing a failure. So I guess what I'm going to do is replace a piece that I replaced like 3 weeks ago AGAIN...

Is anyone familiar with the idea that the ICM can damage the CKP sensor?

No, but the ICM is a problem across the GM brands. I'd bet on a failed crank sensor, though.

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One Big Ass Mistake America

i have gotten DOA parts. just becuase it's new down not mean it works

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92 LeBaron Convert: Turbo 3L 97 Grand Prix GT 4dr "Frankenstein": L67 4t65 swap
97 Grand Marquis: Summer DD 99 Grand Prix GTP: Top Swap Beater

True, well I went out to start my vehicle today and it turned over, then died, now it won't turn over at all, all I hear is click click click for as long as I hold the key. I'm worried.... keep in mind, I changed the ICM recently and did not change the CKP, however, I planned on changing the CKP on monday, but I'm thinking I'm now going to have to pay a f*c*i*g towing bill=\ (so frustrated atm)

when you change the ICM do you have to use thermal paste to keep it cool? None came with the part that I purchased. Also, is it possible the ckp is dead and that is why I can't start the vehicle? Or should I be looking into starter troubleshooting etc..

appreciate your guys input. seriously helpful. I'm hoping that at some point I'll be able to post SOLVED... for anyone else having this trouble, as this issue seems to have no definitive answers

If the CPS is bad it usually shows some signs of going bad first. While driving the tach will drop to 0RPM's (even though the car is still running). I mean it could be bad but there's really no way for us to tell for sure. Hopefully you get this sorted out soon man.

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'05 WRX STi - COBB Stage 2|Invidia DP|3" Borla XR-1|Coilovers|Camber Plates|Swaybars|Endlinks|Bushings|Braces|Anti Lift Kit|DBA4000s|SS lines|
Sold: 06 Cobalt SS/SC, 99 GTP 245WHP/326 Ft-lbs, 06 R6

well, I've read quite a few times that CPS will produce an effect like that, yet I have not seen it act up like that. So far, It seems the shadetree mechanic that did my labor must have not placed my terminal correctly back onto the battery..... producing the same exact problem but because of a different issue.

so far I am driving and its awesome, but before I post the exact [SOVLED] on this issue I'm going to do some testing. Feels nice to finally have my house key on the same ring as my car keys lol...

i got a REAL EASY FIX:)

some gas, and a lighter, TADA..........

sorry i couldnt help it;)

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I have your answer...put in a battery and check your connectors for corrosion...when you said you went out and all you heard was tick tick tick as long as you cranked it...it sounds like a dead battery...however if it starts sometimes it can't be dead but certainly a connection. Though your car runs off the alt. Once started the battery gives the car its ground without power and ground you have no current flow. Check the connections at battery and follow the big ground wire down to wherever it goes...prob the starter or block and clean it there too.

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2000 Silvermist GTP. CAI, 180 t-stat, stage 2 shift kit, u-bend and resonator delete, fastkatt tuned PCM, autolite P104's, 3.4 pulley, altenator wire upgrade.

Hey thanks again for the suggestions. Well, after having the ICM changed and the terminals cleaned. The car died yet again.....

I had it towed once again, and found that I had a bad fuel pump. It was installed last year, and died within warranty so the repair only cost me labor. I'm currently driving again and everything seems good! Also, the ICM does not need thermal paste.

If you ever have a stalling / intermittent failure with your Grand Prix, I highly recommend checking your components in this fashion:
Ignition System-
1. Spark Plugs
2. Coil Wires
3. Ignition Control Module
4. Crankshaft Position Sensor
5. Camshaft Position Sensor
Fuel Delivery System-
1. Injectors for fault - typically trigger codes
2. Fuel Pressure / fuel pump - we sprayed ether into the chambers and it stayed on until the ether burned out. Signaled a dead fuel pump.

That's about as far as I have gotten. Again, my repairs were just done so I'm going to update ONE MORE time before I post it's solved. I hope this helps someone!

6/8/2011 - Engine dies

Has the fuel filter been changed recently? Also I have had issues with the fuel pressure regulator on another 3800 powered car.

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1999 GT|SLP CAI|Borla Catback| Shift kit|18" Koblenz|GMPP Lowering|GMPP handling|Blk Headlights|ER Rcokers|HV3|HV TB http://www.fquick.com/The_Guz