2001 Sonoma radiator fan speed

gmc

#1

I’ve never really understood why the radiator fan needed to rpm with the engine when cold, but regardless, it’s going on way too long now. I have to drive it a mile or two before it settles down anytime the engine is below 200 degrees. I seem to lose pick up with this going on and all the noise is no fun either. For a short time after this started I had engine light code P1416 come on (Secondary Air Injection (AIR) System). The check engine light went off by itself after a couple days and has stayed off. Don’t know if this might have anything to do with my racing fan. If anyone has any thoughts on this, would sure like some help.


#2

I can’t even tell what you are describing, but I assume it is a noisy cooling fan, and perhaps one that is running when it shouldn’t be. Unless your A/C (or defroster) is running, the fan shouldn’t run at all when the engine is cold. It is probably supposed to kick in at a coolant temp of something on the order of 220240 degrees or so. Note, however that the fan should run whenever the A/C is on, and that will happen automatically with the defroster running.

If you want to provide a complete description of what is going on with the truck than could help. But it sounds to me like your cooling fan might be bad, and its control system needs to be evaluated.


#3

Hi Walt. Your truck has a mechanical fan driven by the belt. The thermostatic fan clutch will “lock up” the fan when it sits for awhile. Power loss is certainly noticeable when the fan clutch is locked. It is possible a new fan clutch may relieve your complaint or improve it to some degree.

The fault code for air injection is unrelated to the sticky fan clutch.