Thread: 00 Grand Prix Won't stay running/start

So here's the deal. I've been having this problem for a month. It started when my car shut off while driving. I was able to restart the car after I pulled the ECM(sense) fuse with the car in the on posistion and putting it back in. It got to a point where it would only drive 1.9 miles or a half mile at a time. After replacing the CPS it will start and shut off 30 secs later. You can't restart the car unless you disconnect the battery and wait 10 minutes to reconnect it.

So far I've checked the Ignition Control Module for cracks and other faults, replaced my fuel pump (with a Walbro 255), cleaned my MAF, bought another ECM and replaced the Crank Position Sensor. I've also tried starting the car with the MAF unplugged. None of this has worked. After I replaced the CPS the Service Engine Soon light shut off.

I'm tapped out of ideas.

Have you checked the ground and positive cables? If there is rust on the connecting points it can make it hard to start or will not start. The cables may have corrosion on them not letting it start/stay running.

I just thought when you replaced the ECM is that when it actually stopped running after 30sec? Why I ask is with VATS enabled on the ECM it might think that you are stealing the car and disable it after it starts. Try putting the old one back in.

sounds like a security issue

All the grounds on my car are great. I replaced the ICM and put back in the orignal ECM. The car started. It sat there and idled for a good 30 minutes and then I drove it a good 15 minutes. Had absolutely no problems. Shut it off at the gas station and filled the tank. It wouldn't start back up. I did notice that the top part of the engine was incrediblely hot. My temp reading was in the norm and no trouble lights where on.

It turns but doesn't start.

Then do you have fuel and spark?

So does the fuel pump prime when you turn the key to "ON"?

Just checked the fuel pressure. It is not priming, again. There is spark. I'm going to order a new pigtail for the pump. It seems too intermitten on working or not.

Installed new pigtail. Still no fuel. Triple checked all the wires from the pump to the body. All is well there. Disconnected the battery and waited x amount of minutes. The car started. Drove it home. Now it won't start again. Any idea what sensors tell the ECM to shut the fuel off?

PK3 system does

Did u check relays? when a faulty relay overheats it tends to fail, burnt prongs and excess voltage do that also... Good luck

Yes I checked the relays. And there is no security light to indicate a problem with the PK3. Does that matter?

It came down to taking it in to the dealership. I only agreed to do this since they said it's only $79 dollars to reprogram the ECM (which they look at and said didn't need to be done or to run diagnostics. That's a hell of a price drop from a couple years ago.

The diagnosis from the dealership came back as a bad fuel pump connector. Replace it. It helped, a little. All that did was make it so I could pull the ECM sense fuse to reset the whole thing, making it prime the fuel system. Still can't drive the car more than a mile at a time. So they're doing it again, for free.

After weeks the dealership asked for the other PCM to reflash it for my car. It didn't work. Now they've given up. They're just as mystified as me. Anyone have any ideas at all?

So one day the SES light comes on. The car quit shutting off. Checked the codes. Errors are the MAP and EGR. I'll replace them eventually. But now that it's running I'm not in a hurry.