roughly one minute after i start the car when the engine is completely cold, both the ac and cooling fans will kick on.

both fans turn off when unplugged from their respective relays. thermostat has been replaced, new water pump.

i will probly be changing the temp sending unit in the morning.

the temp gauge will sit exactly in the middle of the gauge. i would think with both fans on the coolant temp gauge would be lower then the middle of the gauge.

any help would be nice. thanks.

 

AC fan only comes on only when the AC is on.
Also, when AC is on, BOTH fans come on.

If car gets warm without the AC, then only the radiator fan will come on - never the AC fan.

 

replaced the radiator cap and that didnt do anything.

4drEF - ya thats why im puzzled. something is triggering both fans to come on at the same time. the ac isnt on at all.

 

So you are positive that the AC compressor is not engaged?
I would double check - wait for both fans to come on and then turn the AC on and off listening for the compressor clutch to click.

If the compressor is for sure -not- clicking on, then try removing the AC fan relay and see if the radiator fan still comes on prematurely.

 

as soon as i unplug the ac relay the fan turns off. the same with the cooling fan too.

 

i am 100% positive the compressor isnt on when the fans kick on.

 

Nice!
Narrowing down the issue.
Need to make sure your radiator fan relay is working properly.


Remove the A/C relay again (both fans off)
Short the two wires for the coolant temp switch together.

Now turn the key to "ON" (no need to start).
Does the radiator fan come on?

If NO then short both wires from the radiator fan switch to ground and see if the fan comes on then.




Stock location for this sensor is on the back of the motor near the oil filter (oil filter is on the bottom right in the pic)
It is the two prong sensor at the top right
(On a swapped engine, the sensor may be found on the thermostat housing.)

 

problem solved.

the temp sending unit went bad. i got to looking at that wiring diagram and the only thing that stood out in my mind that could turn both fans on was that temp sending unit. i replaced it and now it works as it should.

thanks for the help and posting that wiring diagram. now i got to figure out my tranny problem and now the engine has a small stutter along with a bouncing tac when its at idle. i think that might be the coil cause a wire comes right off the coil to the tac.