Stalling and Starting problems [Archive] - GrandAmGT.com Forum

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bergie44
09-24-2008, 07:07 PM
I have been having a lot of problems with with my GAGT. I believe they are related to the PCM.
A brief history, My daughter was driving along one day than all the lights on the dash got real bright and flashed on and off, all the buzzers and beepers went off and the car died. The cause was the alternator went dead. When the alternator died it must have temporally spiked the voltage very high because several fuses in the car blew.

Since this occurrence I have several passlock issues ( I finally defeated the passlock by installing a resistor on the ignition switch yellow to black wire. This was done after having the ignition switch and all associated connectors replaced.

Intermittently the car will die with no spark coming from the spark plugs. The coil packs and the ignition control module were replaced.Initially after the ICM was replaced everything seemed to work fine for a couple of weeks. Now the stalling and starting problem is back. It is always a "No Spark" issue. The fuel pressure is fine I have monitored it every time it failed to start.

The bottom line all this started after the alternator went out. and blew the fuses.

I am leaning toward the PCM. It must have taken a hit after the alternator went out.

Does any one have any other thing to offer. I am willing to listen to any advice.

bergie44
09-25-2008, 06:09 PM
I am leaning towards a 7X sensor after doing some searches. I would also like to install a PCM from MP Racing. But I want to make sure I fix the problem first or know the PCM is the problem before I replace it. Is there anything I need to do after replacing the 7X sensor?

bergie44
09-25-2008, 07:00 PM
one more thing, where is the 7x sensor. From the searches I see it should be on the back side of the engine. However when I follow the yellow and purple wire comming off the ICM it goes to a sensor on the transmission. I have a 99 GAGT. I believe the 7X sensor goes directly to the ICM, Correct?
Please let me know.

bergie44
09-27-2008, 01:44 PM
OK, In case anyone is interested. It turned out to be a two-fold problem.

1st; the 7X Crankshaft sensor was leaking internally. When I took the connector off the sensor there was oil on the inside. The outside was dry.

2nd; The camshaft sensor was bad. The LIM leaked above the sensor and also I had a power steering pump go out spilling fluid on the sensor. One or both of the leaks caused the wire insulation to melt.

Both of these caused intermittent stalls and problems with not starting, but no codes were ever thrown!!!!!

Always the problem with no starting was no spark.

gagt Mechanic
09-27-2008, 10:32 PM
alot of times if the crank sens goes out, the pcm will take cam info and visa versa. I beleave that they are double fault codes. so depending on what is going bad and when or how it is faulting, low voltage, high voltage or no sig, it could be a while for a code, especially with contamination. with both contaminated, you are just unlucky.