E-Fan Keeps Motor Running

[rico05]

I just switched to a Zirgo 2700cfm 16" fan, and it cools really well. The issue is, I have the relay switched off of the EGI Pump in the main fuse block (like everyone reccomends) For my previous setup (Altima fans) there was no issue, but now, the fan runs for a few seconds after the car is shut off, and the fuel pump continues to operate, making the car studder for a few seconds then die...all AFTER the key is out. Any ideas? Am I stuck operating the fan off of a switch or a thermostat? A buddy suggested running a resistor, but I have no clue what all that entails. Thanks for any help.

[AmoebAssassin]

A resistor really wouldnt help in this scenario.

You're better off running the fan off a thermostat anyway. A switch is too easy to forget, and if you get caught in traffic with your fan off...pwned. Plus, I think Pep Boys/Autozone/Advance sells fan thermostats pretty cheap.

[rsmithdrift]

Somebody told me that if your fan is on the same circuit as the fuel pump that when the fan spins with the car off it'll acutally create a positive charge and feed it directly to the fuel pump. You need a relay......not a resistor.

[rico05]

Like I said in my first post, the fuel pump is the switched 12v for a relay that provides power to the fan.

I will go for a thermostat then.

[benemorius]

That's pretty funny. About the only possibility is that the spinning fan is actually acting as a generator when the relay switches off. Anything run from that relay will be receiving this voltage from the fan until it stops. This is generally a bad thing as it may potentially damage anything connected to that relay. The solution is to run a diode in series with the fan. This will allow current to flow into the fan, but not back out of it.

[rico05]

Well, I just decided to not be cheap (that's a first) and I bought a matching Zirgo adjustible thermostat. Thanks for the help.