1specman

My son's 08 f150 is overheating while drive in high trafic conditions. he seems to think it is a/c related but nt sure. he is certain though that is does not overheat while interstae driving.

techrep

iTrader: (1)

with the a/c on the motor works a tad harder.. that is not his problem though.. i would start with a good system flush and while your performing the flush remove the T-stat and when done install a new T-stat and fill with motorcraft gold and distiled water

lewissa81

Also check the fan clutch. It should have some resistance when you turn it by hand. If it spins freely, it's toast.

1specman

yeah, i figured the fan clutch too.

there are wires that go to the fan clutch. what do they control and how do i verify the signals?

lewissa81

I forgot about the later electric fan clutches. Ignore my last post. The pcm controls when the clutch engages and disengages. I've never had to trouble shoot one, so I'm afraid I won't be too much help for you.

1specman

thanks anyway. i'll keep searching