Turned Ignition Key Off and the Engine Continued Running

[joelittel]

Tonight I turned the ignition off and the car continued to run. A quick internet search revealed that this could be a faulty switch, poor quality gas, timing that's too far advanced and a few other issues.

Have any of you seen this sort of thing before? I did recently replace my ignition switch with one from Mr. FIAT

[RRoller123]

How well did it run? Like there was no difference? Or did it stumble along?

[daved]

My question also. If it runs normally would think there is a problem with the switch or installation. If it doesn't quite shut off & idles very slow & rough I think they called that dieseling, ignition is shut off but gas is still ignited by hot carbon deposits in the engine.

[joelittel]

It ran along like nothing was wrong. No hesitation or stumble. Quite smoothly actually.

I just read that incorrect spark plugs can cause this and i did recently replace the plugs too.

[vandor]

If it's incorrect plug, dieseling etc., then it would not run smoothly, but would be stumbling.
If it continues to idle fine then the coil circuit isstill energized.

[AriK]

Incorrect spark plugs or ignited carbon deposits will cause the engine to diesel or percolate.
What you are describing is that you can continue driving it after shutdown. Try disconnecting the pink wire at the coil (+BAT), if it stalls the motor, chances are you have a faulty ignition switch.

[spider2081]

there have been a few posts with the same issue. The cause for them was a defective alternator voltage regulator. If you shut off the ignition switch and the car keeps running pull the black/violet spade connector off its terminal at the alternator. If the car stops running chances are the alternator or voltage regulator are defective.