Randomly stalls and can't find the problem!

Maintenance/Repairs
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1

Weeks ago, I was waiting for someone with my car idling and suddenly it just stalled. The battery power was still on but the engine died. When I restart it, it starts up but then dies after a few seconds. After trying 3-4 times it no longer starts. I had it towed to the repair shop and by the time they went to look at it, it started up just fine. A few days later I was driving (like 1 min from my house) and the car engine died, again the battery was still working. Power steering was gone. I coasted off the road and tried to start it–again it would start up and then die and then after a few tries it no longer starts. I had it brought to the repair shop. Again, it started fine for them but they changed out the battery just to see. I also had fuel cleaner put in the gas tank.

Just to be safe, I brought it to a dealer since my normal mechanic couldn’t find anything. At the dealership they ran codes and didn’t find any. They said that sometime the lines to the cams or crank get corroded but that mine looked fine. Since it wasn’t doing it for them, they didn’t have any other recommendations.

Everything has been fine for the last few weeks and then I went to start my car last night. It started fine even though it’s really cold and hasn’t been driven in a few days. While I was scraping the car, I could hear the engine turn off. When I re-started it the same pattern happened–restarted the first few times and then died and then wouldn’t even start.

I don’t even know what to do at this point since it only seems to happen close or at home and not for repair places. Anyone have other ideas of what to check?

2

Intermittent loss of crank position sensor signal or intermittent operation of idle air control (IAC) valve seem likely. Another might be intermittent power in fuel pump circuit or perhaps a dying fuel pump. The best way to catch it while its doing it is probably to get it in a scanner to monitor the computer & engine activities.

3

They did check the fuel pump and they said it looked good. Is getting it in a scanner different then have the dealership run the diagnostics?

4

Have you tried depressing the accelerator pedal to see if it will restart? If the engine will restart while doing this then there could be a fault with the Idle Air Control valve circuit.

If the vehicle dies at road speed or refuses to start with the pedal depressed then it could still be the fuel pump. Fuel pump do not always have a hard failure. It’s very common for a pump to randomly die and then start working again for an undetermined amount of time.

There is really no way of testing this except by noticing a slight anomaly in fuel pressure (maybe too slight to even notice) or by checking the current draw of the fuel pump. The latter could mean that the pump is worn and dragging and this causes more electrical current to be used. Even that is a bit iffy and sometimes, as sad as it is, it may take a wild guess and pump replacement followed by a prayer that the problem is solved.

The pump could be even more suspect if the fuel filter is not changed on a regular basis as a partially clogged filter can work a pump to death. Hope that helps anyway.