2000 Volkswagen Golf. The ground from the oil pressure sending is melting randomly. When I turn the car on, it will run with no problem. I turn it off and the key and the wire start to smoke, no crank. I turn the key and it runs fine. I turn the key and the wire is smoking.
The wire will smoke for one particular reason. You've got bad grounding going to the engine, so you'll need to reground it. Run a new ground from the battery's negative terminal to the engine block. When that ground doesn't work properly from the battery to the engine, it will start using the oil pressure sending unit wire as a ground wire. When this happens it will start melting everything out. Pray that it hasn't shorted out the computer yet.
So reground the bad ground and rewire the oil pressure sending unit wire to ensure that it's not melted as well. Bad grounds tend to do this all the time. I'd recommend having a mechanic check that car out to diagnose this wiring problem accurately.
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