Originally Posted by djb383

'98 FSM says the efan will cycle on at 218F coolant temp or when the a/c compressor is engaged. There have been posts that '00-'01 efans only cycle on when coolant temp reaches specified temp and that the dealer can re-program the ECM to cycle the efan on when a/c compressor engages.......like '99 and earlier models.

Originally Posted by Gee oh Dee

Most vehicles that have AC and efans have dual efans, not just single ones. If you only have one efan and have AC it may kick on when you turn on the AC.

On a side note some people who ditch their AC keep the 2nd fan and wire it to a switch so when crawling around off road it can be used for added cooling.

Originally Posted by krazytoy

I have a '99 and it cycles with the a/c compressor and kicks on at about 220.
I also wired the fan to a switch on my dash so i can turn it on whenever, i really only kick it on manually at the sand dunes. Just an FYI

Originally Posted by daurwid

I hot wired my aux electric fan to on at start. I don't like it this way because it causes the engine to continue running for about 3-5 secs after shutting it down and pulling the key. Plan on putting a switch in on the dash so I can turn it on and off manually. It drops the temps down about 10+ degrees easily in the summer heat.

Been thinking about putting in a higher powered electric fan in place of the mechanical fan as well just haven't had the time nor money.

Heh, speaking of fans. I put the blower motor on a switch at the dash so it could be put on a different circuit. Old blower motors when going out tend to pull extreme amounts of juice. At least this way it wasn't blowing 25Amp fuses like there's no tomorrow anymore. LOL

Originally Posted by Gee oh Dee

I recently found a thread here on using a 90-95 Ford Taurus fan. They are some of the highest flowing fans out there, and are cheap.

On a side note, I'm not sure if you worded your post wrong, but wiring something shouldn't cause your engine to keep running after you turn the key off. Something is wrong with your truck.

Originally Posted by solderjunkie

Did you wire the electric fan to run any time the key is on???

The electric fan spinning will generate enough current to keep the ASD relay energized after shutdown for a couple of seconds.