[renaissance man]

Dave,

I have this EXACT same issue as we speak. Here is what I've found so far. when my fan is on (wired to a manual switch on the dash) the car will continue to run for 5-6 seconds after the key is turned off. When the fan switch is off, the car dies immediately as it's supposed to when the key is turned off. Looks like the fan is run to the voltage regulator on the same circuit as my MSD ignition power.

Two things:

1. Wire all of the grounds on your dash to a common ground.

2. Wire the fan or any accessories to a separate fuse used for Accessories at the fuse box.

You have a "loop" that is keeping the circuit closed. Let me know and we may be able to talk through it.

Regards,