A/C has me stumped
 

I have a 2003 Ranger, 4 cylinder. The problem I am having when I select A/C (Normal or Max) it takes about 5 minutes for the compresser to come on. I have put gauges on the compresser all is in the green. It has a full charge, but it takes about 5 minutes for the clutch to engage. When the clutch engages all works normal, cold air. I don't think the clutch is bad, I could be wrong. This has me stump. Any thoughts.... Please

Check the low pressure switch it may be going bad on ya.

check for power at the compressor. If the compressor has power, the compressor is bad. If there is no power, one of the pressure switches, the relay or the a/c switch could be bad. Keep in mind when its cold, the system wont have enough pressure to come on. engine heat will warm it up and cause the a/c to engage

I am having the same issue with an 03 4.0L 5spd. New compressor clutch kit, new A/C switch from dealer, and cools like a champ after driving for 25 minutes or so. What the heck? Have no idea what else to check. I have jumped the low pressure switches and the high pressure switches just to make sure it wasnt one of them, no change. Also system is full of freon...

IIRC the PCM shuts off the compressor at WOT (wide open throttle) .
Check the operation of the throttle position sensor.

Well, I checked it, worked. Replaced to just make sure. Still no a/c...