My daughter drives a 2002 Corolla. Occasionally, she'll turn the key off, and the engine will continue to 'run'. She has to work the key a couple of times to actually get the noise to stop.
In this video, she pulls up, and turns the engine off, and the weird noise starts. After a few seconds, she restarts the engine, and it sounds normal. She then turns the key off, and the noise starts again. She finally turns the engine on and off, and the noise stops.

Is this a bad starter switch or starter motor?

This message has been edited. Last edited by: 4x5,

Stuck in "start". From the description, it's more than likely the ignition switch

Yeah, I'd say the start circuit is coming online intermittently. Getting on the battery posts with a meter would probably tell you real quick if that's the issue (voltage drop) . Better still a test light on the starter circuit to see if it's energized when this occurs.

If it keeps up you will likely trash the starter and or flywheel.

Most likely a bad ignition switch or even the starter relay if the starter is in fact getting energized.

Starter solenoid stuck.

a good whack with a hammer to the solenoid will likely get it to disengage but that isn't a fix. rebuild it or get another starter. if you get one from an auto parts store, chances are it's rebuilt so make sure it comes with a lifetime warranty and keep a digital copy of the receipt as they normally print on some kind of thermal paper and the info disappears over time.

This may tear up the ring gear on the flywheel if it hasn't already. That sound is grinding metal. Get it fixed now!

Out-of-control cranking even with the ignition off usually indicates a sticking solenoid (although it could also be something else like a shorted ignition switch or shorted wires). Usually a solenoid sticks in the neutral position, preventing a start, but in rare cases it sticks in the engaged postion and starts too much.

quote:

Originally posted by shiftyvtec:
Yeah, I'd say the start circuit is coming online intermittently. Getting on the battery posts with a meter would probably tell you real quick if that's the issue (voltage drop) . Better still a test light on the starter circuit to see if it's energized when this occurs.

If it keeps up you will likely trash the starter and or flywheel.

Most likely a bad ignition switch or even the starter relay if the starter is in fact getting energized.

This right here.

When the engine is running, is the starter still engaging? if not, I would lean strongly towards a faulty ignition switch.

Thanks everyone for your help. Now we have to figure out if this car is worth putting any more money into.

AS others noted, it's clearly a stuck starter. It may be the start solenoid. It may also be in the start switch.

quote:

Originally posted by 4x5:
Thanks everyone for your help. Now we have to figure out if this car is worth putting any more money into.

As mentioned, whacking the starter/solenoid often frees it, at least for the moment. Some people go years whacking every time they drive out. Even better, it isn't at all hard removing the starter unit and just cleaning it, often returning it to full service- all free, of course.

If the starter does not run when the engine is running, I doubt that the solenoid is stuck.

I would hook my DVOM to the start wire going to the starter solenoid. I should only have power there when I am cranking the engine. My guess is that there is power when cranking, none when running and then power when in the off position intermittently, causing the starter to run. This points towards an internal issue in the ignition switch.

If the starter sometimes runs when the engine is running, look for an intermittent short to power on the start circuit.

I think (though not sure) I can hear the starter actually is still running when the engine is turning, but the sound is fainter. I wonder if the pinion is floating against the turning ring gear. That makes sense since the internal one-way clutch prevents the flywheel from back-driving the pinion when the engine spins up. When the engine is killed, the pinion begins partially engaging again, and the noise is suddenly louder.

That happened to my truck. Before I could get the battery terminal disconnected, the insulation and accumulated grease on the wire to the starter ignited. Luckily, I had a fire extinguisher and I was able to quickly put it out.