I dont think my rad fan turns on. I can drive around all day and will never here the dam thing running. I'll come home and the motor will be hotter than hell. The fan just doesn't move. When I check for codes, I can hear the fan turning then. What can I check here? Sometimes I can smell the heat from the motor area as well (if you know that smell) when I turn on air switch (the car is NOT A/C). Anyone?

 

Do you have gauges or idiot lights? As long as the car doesn't overheat your fine.

 

I have the idiot lights

 

just rig the fan to be on all the time

 

Since you said that the fan comes on when the ALDL has been jumpered for diagnostic purposes, that rules out MOST wiring issues, and the possibility of a bad relay.

Check your fan switch. This sucker is a real PITA to get to, as it is located in the back corner of the passenger side cylinder head, right next to the lifting eye. You can either have a bad switch, a bad wire running to the switch (exhaust manifold!) or both are good but some idiot put sealant on the switch when replacing it and it can't ground out like it is supposed to.

And with kretos' option, you need to run a wire between the tan/white and black/red wires at the relay. Hope this helps.

 

I had the same problem with my 92 RS(3.1). Turned out to be that the wire had got hot and had allmost melted into. So I just spliced in a new piece of wire and presto, problem solved. As long as this thread is going, does anyone know where you could get a different switch to turn the fans on at a lower temp? Just curious?





Max....

 

There's a tech article about controlling the fans and what temps they turn on at, etc. I am currently using one that I found in my dad's tool cabinet, that I would assume was bought for our now gone 87 Firenza. My temp gauge now don't reach 220 before the fan turns on, but I think that either the gauge or the sender or something is going south in the circuit...

Anyways, you can get lower temp switches from GM and a couple of aftermarket sources.

 

First, your fan is made to come on when it's over 220*, so you may Not be getting that hot. There are sensors for this, but I just by-passed them and installed a switch under my head-light **** and installed gauges. When it goes over 200* I put on the fan, cools down to 195* in 5 mins.

 

If I were you, I'd buy an electrical water temp gauge for $20, hook it up to the motor, string the wire behind the hood and thru the door window, tape the gauge to the dash, and go for a drive to see how "hot" your motor really is.

And you may just want to leave the idiot light unplugged and mount the gauge permanently.

The hole for the idiot light "switch"- and where you'd put the "sender" for the aftermarket gauge- is on the driver's side head. It's behind your air conditioning compressor, and it's on the outermost edge of the head, right below the valve cover. It's got a single green wire going to it. Unbolt the a/c compressor just to get some room to work, and use a LARGE (12" or 15") open ended adjustable wrench to remove the factory idiot light switch.

Wrap some teflon tape around the threads of the new gauge's sensor (teflon tape is sold by gasket sealants and costs like $1.50 for a roll). The teflon prevents a coolant leak. Then screw the sensor in, "rig up" the gauge, and go for a spin.

Tip; if you add an oil pressure gauge and disconnect the factory idiot light switch on the motor, your idiot light will always stay on (it sees 0 oil pressure). Just remove the bulb from the dash.