: 98 Deville non-functional engine cooler fan

07-05-08, 01:37 PM
Hello guys,

I have a 98 deville that I have been looking at, for a while now I noticed that the temperature on the IPC says that the coolant gets pretty hot, well over 200 degrees. Not good. Poking around for a problem shows me that the cooling fans on the back of the radiator never turn on! Yikes, can someone give me some diagnostic instructions? The Alldatadiy site seems less than informative about exactly how the fans operate. Thanks in advance, someone here almost always points me in the right direction.

07-05-08, 02:41 PM
One or both cooling fans come on low speed at 224 degrees, high at 236. One fan will run slow in any mode that calls for the a/c compressor to run.

The engine is designed to run at 206-220 degrees: the thermostat starts at 188 and is fully open at 206, so the oil (if you have a radiator end tank "oil cooler") and coolant will always be at or above 200...always. 18 psi cap, 50/50 DEXCOOL is a boil point of 264.

You could double check the fan fuses in the engine room box.....2 fuses and maybe 2 relays, although the relays on a 98 may be down on the fan bracket. (....and it can take a long time for a fan to come on at idle.)

07-05-08, 04:31 PM
To summarize what Sub said, you ain't got no problem. Sounds like it is operating as designed. 200 degrees is FAR from hot.

07-05-08, 05:30 PM
Thanks Guys!