Starter will not disengage

JGANAWAY

MEMBER
1993 FORD F-150
4.9L
6 CYL
4WD
MANUAL
280,000 MILES

At first, when I turned the ignition to start the truck, it only made a thumping sound as if the starter solenoid switch wasn't getting signal. I had the starter tested and it passed but the guy said it sounds dry. I bought a new fender mounted solenoid while I was there. I put on the new solenoid and starter and the truck started but made a loud grinding noise. I went back to AutoZone and bought a starter solenoid switch and it still does the same thing except, where as the old starter solenoid switch was getting hot and making the starter get warm, the new one doesn't.

Sunday, September 26th, 2021 AT 5:24 AM

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

You are correct that the starter solenoid sticking is the likely issue but if you replaced this and it is still doing it then we need to take a step back and start checking voltage to find out if this is being commanded on by a sticking relay.

https://www.2carpros.com/articles/how-to-check-wiring

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

If you look at the wiring diagram below you will see the wire coming from the battery. This should have 12 volts all the time.

The other wire coming from the relay, should only have 12 volts when the key is in the start position.

I would put my meter on this wire and ground and start the engine. If the 12 volts stays there when you let the key go then you have an issue with the relay most likely.

Please run through this and let us know what you find. Thanks

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