The engine cooling fan always seems to be runing in my car (a '95 legacy auto with 96,000 miles). It was 35 degrees yesterday, and I thought it was odd that the fan would be constantly running. Is this normal? The car runs and drives absolutely fine, no CEL or anything, gets up to normal operating temp. (smack in the middle of the gague) and stays there. I can't help but wonder if this is cutting into my MPG. I'm gettin the car serviced on the 13th, should I just mention it then? I had the thermal temp sensor replaced about a year ago due to it causing a CEL. Any thoughts as to what this could be, if anything to worry about?

 

Brian M.

Could be a bad sensor, but are you using your windshield defroster?

The AC compressor runs with the defroster and the cooling fan runs whenever the compressor does.

No, I wasn't using the defroster. What sensor could it be? Like I said, I had the thermal temp. sensor replaced (I checked my records, it was last March) and I have no driveability issues or CEL's. As far as I know, I wasn't even using the fan/heater. I set the control to warm, and let the vent effect blow warm air.

 

Brian M.

Ac comes on for a few seconds when you start the car in cold weather to lubricate the compressor. Thats why there are so few compressor failures now.

You can have a stuck fan relay, or a bad fan switch. the fan switch is in the radiator (i could be wrong). If this is the failure mode for the switch, thats really good. They used to fail so that they never came on and next thing you knew it was head gasket time.

 

 

nipper

The fan is switched on and off by the ECU and the ECU receives it's info from the coolant temp sensor. This is how it is in my 96 Legacy. I suppose it's the same for the 95 model, but I'm not sure.

Possibilities:

1) bad sensor

2) stuck fan relay