Engine continues to run after key turned off

[jsz]

Finally got the ignition issue resolved and the car started. When car is started and the key is turned off, the car continues to run. I fully disassembled the ignition switch cleaned the contacts and reassembled and it still will not shut off. So we stared the car and with the car running disconnected the pink wire on the ignition switch, ( which feeds the L Blue/ Black + coil wire) and it still ran. We then tried removing the ignition relay and again the car did not shut off. I am wondering if I am back feeding power, possibly something on the alternator was installed incorrectly.
Could anyone help detail how the engine is shutoff? I am assuming power is cut to the + side of the coil
Thank you again.

[AndyVAS]

It's probably the alternator wiring. Try pulling the exciter wire off the back of the alternator and see if that does the trick. If so, you have found the problem.

[18Fiatsandcounting]

A few thoughts. If you have a voltmeter, you could measure the voltage between the + connection on the coil and ground. With the ignition switch in the off position, this should be zero volts and about 12 volts when the ignition is on. The engine can either be running or not for this test. If you get 12 volts with the ignition in the off position then you've got something wired wrong so that power still gets to the + of the coil. If you don't have a voltmeter, another test would be to start the engine and pull the center wire from the coil to the distributor (suggest with gloves to avoid a shock from a leaky plug wire). If the engine keeps running, let us know as there are only a few (rare) things that could cause that.

-Bryan

[jsz]

Thank you, both. Will look into those things. The exciter wire on the alternator, would that be the black / violet wire on a 78 model?

Thank you again, will report back.

[SteinOnkel]

Thank you, both. Will look into those things. The exciter wire on the alternator, would that be the black / violet wire on a 78 model?

Thank you again, will report back.

That's the one.

Are you running an electronic ignition? A few cars I've owned that went from points to electronic liked to run on. The alternator would back feed 7-8V, not enough for points ignition to keep running, but enough to hold a relay open etc. The fix is to solder a diode into the exciter wire.

[jsz]

Well tracked down the exciter wire, ( black / violet) and it was not hooked up to the alternator. Another wire from the fast idle cycle was, or at least that is what I think it was. Reconnected the black violet and everything works as it should.

Thanks again for the help.