Ignition weirdness

[Power Surge]

My CSX is doing something odd lately. When I turn the car off, it will actually run for 2-3 seconds after I have turned the key. I don't mean run on or dieseling, I mean it will stay running like I never turned it off. Flick the key to off, and it shuts off 2-3 seconds later. Anyone ever come across this? Bad ignition switch maybe?

[HighPlainsDrifter]

Hi Sal,
If you have an msd ignition, then the ignition is running off the alternater backfeed. There are a couple ways to stop it. The best way is to take the output of the alt and run it directly to the battery, also isolate the fan power with a relay .
Good Luck,
Perry.

[Barnsnake]

If you have a "charge" light on the dash, MSD supplies a diode to eliminate run-on.
http://www.msdignition.com/1troub1.htm#runon

[Power Surge]

Nope, no MSD and I took the charge light out of the loop already.

I am wondering of the Spal fan is backcharging the car, keeping power to it for a few seconds as it spins down. I'll have to try it with the fan off and see if it makes a difference.

[slithering]

Sal,

A diode will cure the run on, but if you have never had the problem before, you may want to have the alternator checked.

Chris