Good Evening GM family,

I have a quick question about an issue

My 2004 SE at only 90,500 miles has been stalling on me intermittently. It usually stalls when stopped at a red light and while driving anywhere from 30-60mph. I've had the CAM and Crankshaft Position Sensors replaced about a year and a half ago when I previously had this problem. Recently about a month ago my car began stall again. Turned out to be the MAF, I replaced it with an AC Delco MAF. It drove fine for a month and didn't stall until about a few weeks ago. When it began stalling it would start right up again. But last week it stalled on me and would not start up. When I had it towed to my mechanic it started right up at the shop. Each time the car has stalled, I have had the A/C on recirculate so I believe the stalling has something to do with something getting hot and shutting off power to the engine. I even brought this car to the dealer and they couldn't find out what'* wrong with it.

I have no idea of what it could be. I'm thinking it could be the ICM, which was already replaced at 62,000 miles. It could also be the Crankshaft position sensor failing again or even the PCM or ECM.

I'm thinking of getting a heatgun and letting the ICM heat up a little extra while running, to check if it stalls.

I forgot to add, the car is throwing no codes.

Was wondering if anyone else has had this problem and if anyone has any possible solution.

I would greatly appreciate any advice. I really like this car and do not want to get rid of it.


Thanks

Has the IAC & or throttle body been cleaned? (IAC controls the idle)
From a scanguage OBD2 reader, what is the idle rpm reading with AC on?
Does it suddenly drop a bit then stall?
Also add have you done tune up, new plugs, wires, fuel filter? Fuel pressure reading?
Also check fuel pressure regulator, disconnect vacuum line run car for 4 minutes with line plugged and off.
Look for any fuel dripping out of FPR.

When it stalls is it coughing and sputtering, or shutting down like someone flipped a switch. If it shuts down like flipping a switch it is likely a bad crank shaft position sensor ... one of the top 10 common failures with the 3.8 in the Bonneville.

Thanks for the help! When the car stalls, it does shut down immediately like someone flipped a switch. Recently I cleaned the throttle body, but unsure about the IAC. The fuel filter was replaced about a year and a half ago and plugs and wires appear to be in good condition. Is there a possibility it could be the ICM, PCM, or ECM that is heating up and causing the vehicle to stall. I'm definitely going to look into the crank position sensor.

Also is it essential to replace the CAM sensor when replacing the Crankshaft position sensor. I know the two sensors work together.

No......

I usually found, when a crank sensor was the problem, it wouldn't restart right away......

I am leaning towards the throttle body/IAC cleaning....also, check the vac line to the fuel pressure regulator for the presence of fuel......can also try tapping the MAF sensor when warm.....

I had a oldsmobile that would shut off while driving 50-70 mph like someone just flipped a switch. It was the screen on the fuel pump that had a dirty place on it that would suck up to the fuel pump and starve the engine.

next time try unplugging the MAS and see if it starts back up

I think he meant MAF.....