Questions about OEM electric fan.

[Snorman]

I'd like the car to run cooler. I put in a 160 t-stat a few weeks ago and started using the SM this weekend.
In general, when cruising, the car is in the high-170's to low-180's. In traffic, or after whacking on it a few times, the temps climb to the high-180's to mid-190's. I've noticed that the fan is rarely kicking on when this happens.
Is the fan set to kick on the low setting at a certain temp...and if so...what is it? What triggers the high speed relay? When I shut the car off, the fan will kick on after a minute or two and run for a few minutes. Why wouldn't my fan run when the car is running and has reached the aforementioned temps? I just replaced the fan relay. Will a chip change when the fan kicks on? Can I just hardwire the fan to run when the motor is running?
Thanks.
S.

 

[blackbuick87]

The fan turn on point is burned into the chip.

You can run a wire from the fan delay relay and have a switch so you can manually turn it on and off if you want.

Your radiator may be getting plugged or tired also

 

[TurboDave]

Originally posted by Snorman
I'd like the car to run cooler. I put in a 160 t-stat a few weeks ago and started using the SM this weekend.
In general, when cruising, the car is in the high-170's to low-180's. In traffic, or after whacking on it a few times, the temps climb to the high-180's to mid-190's. I've noticed that the fan is rarely kicking on when this happens.
Is the fan set to kick on the low setting at a certain temp...and if so...what is it? What triggers the high speed relay? When I shut the car off, the fan will kick on after a minute or two and run for a few minutes. Why wouldn't my fan run when the car is running and has reached the aforementioned temps? I just replaced the fan relay. Will a chip change when the fan kicks on? Can I just hardwire the fan to run when the motor is running?
Thanks.
S.

Depends on the chip you're running and what the fan parameters are set to. The stock chip for example isn't even programmed to turn the fan on until 192º.
And regardless, the high speed fan relay only kicks on when the A/C is turned on or coolant temps top 213º.

 

[Donald McMullin]

TurboDave:

I found the location in the chip which controls the low speed fan (3F0 Fan-On and 3F1 Fan-Off), but I can not locate where the control in the chip for the high speed fan is.

Does the chip control the high speed fan operation or is this controled by a switch in temperature sensor??

Deep Enough

Donald McMullin

 

[TurboDave]

Originally posted by Donald McMullin
TurboDave:

I found the location in the chip which controls the low speed fan (3F0 Fan-On and 3F1 Fan-Off), but I can not locate where the control in the chip for the high speed fan is.

Does the chip control the high speed fan operation or is this controled by a switch in temperature sensor??

Deep Enough

Donald McMullin

There is no dedicated temp on/off controls in the PCM for high speed fan operation. When the A/C is active the high speed fad relay is activated. The high speed fan relay is also activated by the high temp switch on the intake manifold. The one on the driver's side (single wire).


BTW most folks just wire across or remove the fan resistor so the fan is on high speed any time it's running. Doesn't hurt a thing.