Can someone tell me which sensor on the center head that controls when the electric fan comes on on my 1986 305 TPI Iroc?


Which one of those boys controls the fan? If you have a picture it would be even better.

Thanks

Jamie

 

not sure on your car, cause mine is a 350 but on mine i belive the passenger side sensor in the head controls the secondary fan, and the one on the driver side in the head is the temp. sensor...hope this is right someone can confirm this it may be different on your 305 but i just thought i would tell you...

 

If the fan is mechanically controlled, there's a coolant temp switch in the pass side head between spark plugs 4-6. Replace it with an aftermarket piece with the on/off temps you want and you're in business.

If the fan is managed by the ECM it's another story. The coolant temp sensor is in the front of your intake above the water pump, it sends data to the ECM which uses a lookup table in the PROM to determine whether the fan should be on or off. Easy to change if you're into PROM burning.

 

I know this for sure it is in the lower intake. which one is it though?

 

The fan switch IS in the passenger side head. The coolant temp sensor is in the front of the intake manifold.