I have a 2001 f-150 5.4 triton, 71K.

I am having a problem with the ac compressor, the ac is not working, with the engine running and the ac on max I can watch the ac compressor pully spining smoothly with the serpentine belt but the clutch will engage (spin) for a second or two and then turn off for a second or two. Repeat. It is surging, also the R134a pressure is surging as well, in-sinc with the compressor kicking on and off.

What needs replacing, the entire compressor, the clutch, a sensor?

Thanks for the help

 

Low freon.

Check for leaks, repair and recharge

 

Hey there, I had the same problem as the OP.

The AC Clutch spins on for a few seconds than shuts off, in a repeating cycle as long as the AC is turned on, with the AC blowing hot in the cab.

I bought a can of R-134 and hooked it up per the instructions. The can didn't seem to empty at all, while the needle gauge on the hose coming off of my can jumped up and down with the surging of the ac clutch.

Any ideas?

 

Wear safety glasses...a splash of refrigerant in the eye can blind.
With R124a refrigerant hooked up properly to low side port and engine off, dunk refrigerant can in warm water and open tap. Warm water will turn refrigerant in can to gas and raise pressure so it flows into a/c system. When refrigerant is flowing, can will get cold. When can is half empty, start engine, a/c on max. Add refrigerant until low side pressure is about 35 psi.
This assumes that system is just low from normal leakage.

 

Great, I will try that. Is the AC clutch cycling on/off a normal symptom of a very low freon AC system? The truck was a former fleet truck and I bet the AC was run constantly...

Thank you!

 

A/C system is sealed. Any leak is not normal. Also it does not matter how an a/c is used, if no leak is present refrigerant does not get used up.

 

What percentage of cars on the road with more than 50,000 miles have 100% of their original refrigerant? I'm talking about literally, 100%, not a microliter lost.

I would bet you would not be able to find a single car on the road that hasn't lost at least 1 milliliter of refrigerant.

So what's normal?

 

So I followed your recommendation but the can still didn't seem to be emptying.

I took a video of what's happening:
The clutch appears to be cycling on and off every second.

Any tips would be much appreciated.



Thanks.

 

Where would you "lose" it. It is a sealed system. Do you understand what that means?
You are right about a car not having all there original refrigerant. But due to leaks, not using it. Normal is a system with 100% refrigerant and no moisture in system. Even your house system should have be full of refrigerant because it does not "use" freon either. Rest assured that any ac system that is low on freon has or had a leak.😆

 

+1. Refrigerant doesn't just disappear.