Is it the fan clutch??

[jay90GT302]

I haven't been able to cure my surging idle in the past month or so but the latest issue is the fan speed increases dramatically when u increase the rpms So could the only reason be is that the fan clutch is not disengaging or could it be something else?

 

[tiptop]

i think its normal

 

[93 LX]

the fan will speed up when you rev the engine. What the clutch does is when you are driving the fan will disengage or be allowed to spin slower due to the clutch.

 

[jay90GT302]

yeah it should increase speed but its noticeably different then it was weeks ago, its really fast and loud now and then slows when you shift and then gets very loud again

 

[ill advised]

Has your running temp changed at all? I'm guessing the main thing that would cause a normally loose fan clutch to tighten (bringing more fan noise) would be higher engine temps or the thermostatic spring may be going bad.

The clutch in my '92 is tight at start up but it tends to loosen up after a few minutes.

 

[HISSIN50]

Ambient and actual air temps through the radiator also play into how the clutch acts. In other words, it will act different when the engine is at temp vs when the motor is cold. I didnt see you note when this occurs or any differences between the two.

Good luck.