I have a 2001 Ford F150 with 5.4 V8. The A/C quit this am. I added a can of freon this evening. When I start the truck, the compressor kicks on for about 20 seconds or so and then stops. Ocassionally it will kick back in for a few seconds and then stop again. I can feel the line beginning to cool, but then the clutch disengages. I tried a jumper wire in the high pressure switch and no change. It got dark on me and I did not get to try the low pressure switch (I believe it is on top of the evaporator canister). Any ideas...or anyone else ever seen this problem?

 

Along with making sure there's a correct fill, and checking voltage through the cycle/pressure switches/connectors, make sure the air gap on the clutch is within specs.. To wide and the clutch has trouble pulling to a lock. If you loose current to the cycling switch, check power distribution..

 

Thanks. The air gap is greater than .033. It only has one shim in it, If I remove the one shim the air gap is less than .014. Do you think I should replace the entire clutch assembly?

 

I rechecked the voltage at the compressor and after 15 - 20 seconds it stops. That is why the compressor stops. If you restart the truck it has power to the compressor again but for only 15 - 20 seconds. Any Ideas?

 

I hope you meant R134. I haven't heard you mention gauges. If you don't have enough R134 in it the low side pressure will get too low and the compressor will kick off.