Rigging the Fan on an LT1

[FormulaSlickG94]

I would like to either put a fan switch on my 94 Formula or rig it to run all the time. How would you go about doing this on an LT1? Anyone have any useful links or anything? Thanks!

[TraceZ]

I would like to either put a fan switch on my 94 Formula or rig it to run all the time. How would you go about doing this on an LT1? Anyone have any useful links or anything? Thanks!

Why would you do this? Is it overheating? If it is, you should fix the problem instead of rigging it.

If you want to manually turn on the fan you can jump the relay under the hood. I used to do this after I ran the 1/4 and needed to cool off in the pits.

[Jeff_in_Atl]

Here is a diagram on how to add a manual fan swith on an OBD1 car. http://shbox.com/1/fan_sw_diagram1.jpg
http://shbox.com/1/fan_schematic_1995.jpg

[FormulaSlickG94]

Thanks for the replies! Big help...I will look into it. Here's the problem. When the car gets hot (like at 210+) It just stays there and won't go back down unless I start driving, the fan won't kick on on it's own. At that point the car would get vapor lock and start bogging. We put on a new water pump, intake manifold/injectors, Ignition Module, TPS, Fan Motor, Coil, Alternator, fuel pump, opti, coolant sensor, and the problem was still there but only after the car hits 210 degrees.

Now here's the thing. Yesterday I decided to disconnect my MAF sensor b/c I know that will kick off the fan to run a little experiment. The car ran flawlessly all day...in fact, the car was running smoother than it ever has and it didn't exceed the first temp line. Bottom line I've dumped a lot of money into resolving this problem and it's stressing me out...I really don't know what else to do and I'd like to make it go away for awhile.

[Injuneer]

I'd still try and find the problem. If you are getting vapor lock at 210degF, there is something wrong.... probably with the fuel system, or something hot too close to a fuel line. Vapor lock should not be a problem in a fuel system running at 43.5psi.

And your stock fans won't start to come on until 226degF, unless you reprogram them.

[FormulaSlickG94]

Thanks Fred,

The next thing on my agenda was actually changing the Fuel Pressure Regulator...maybe that will help. Unfortunately this car is my daily driver as well so I need it to run for me so I can get to work/school so I guess in the meantime I will just run the fan to at least deter the problem. Thanks for the reply...at least I can start aiming more at the fuel side.

[Jeff_in_Atl]

Just a bandaid that might help get you by, leave your A/C on. The fans will come on when the A/C comes on.

[Rob B (shoebox)]

I highly doubt the fans or temp had anything to do with your problem. More likely the fact that you were running in speed-density mode with the MAF unplugged.

[TraceZ]

I highly doubt the fans or temp had anything to do with your problem. More likely the fact that you were running in speed-density mode with the MAF unplugged.

I agree. If it runs fine with the MAF unplugged, replace the MAF.