DEAR TOM AND RAY: I have a 1979 Jeep CJ-7 with a 5-liter V-8 engine. The ignition switch is the type commonly used in vehicles of this vintage, located on the steering column. It has an “accessory-only” position; an ignition-on, “run” position; and a spring-loaded, “crank” position, which activates the starter motor as long as you hold the key there. When I go to start the engine, I turn the ignition switch to the “crank” position, and the starter motor cranks normally. But the engine will not start until after I release the key and it springs back to the ignition-on, “run” position. I wired a remote starter switch directly into the starter solenoid and tried starting the car with that. And as long as the ignition switch was in the “run” position, I could make the starter motor crank and the engine fire up normally while the starter motor was still turning. Any ideas? – Michael
RAY: The first thing I’d suspect and test would be a bad ignition switch in the steering column.
TOM: What you want to do is test that “crank” position. When the key is in the crank position, both the starter motor and the coil are supposed to get power.
RAY: The starter motor, obviously, gets power get the engine turning. And the coil gets power to fire the spark plugs, so that once the engine starts turning, it will “catch” and keep running on its own. You’re obviously getting juice to the starter motor in the “crank” position, but maybe not to the coil.
TOM: You can find out with a test light. Hook up the light between the negative terminal of the battery and the positive (ignition) side of the coil. Then turn the key to “crank.” My guess is that nothing will light up.
RAY: That suggests that the ignition switch is bad. So your next step would be to try a new switch.
TOM: But try the switch without installing it first. You should be able to reach under the steering column, unplug the wires that go into the existing switch and then plug those wires into your new switch, which you’ll leave dangling from the wires for now.
RAY: Then use a screwdriver to turn the new switch and see what happens. If it works, you can then remove the steering wheel and install the new switch permanently.
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