The low pressure reading after leaving the expansion valve is around 30 and the high pressure before the expansion valve is 150. The clutch does engage and disengage but only when the ac is turned off in the car. When the ac is on, the clutch is always engaged it never cycles. The condenser is hot and the air in the car is blowing outside temp. The blend door actuator works. Please help.
3
-
Does any cold air come out on the first startup of the day with a cold engine? Blend door actuator works but the blend door itself could be stuck open and mixing hot and cold air unless the engine is cold. Also, is any A/C tubing anywhere getting cold? Check insulated lines for cold.– MTACommented Jun 20 at 12:30
-
The pressures mean nothing unless we know the ambient temperature when testing. Also, if the A.C. is truly off, the compressor should not engage at all.– JupiterCommented Jun 20 at 13:06
-
To my knowledge the first startup of the day does not give cold air but to be honest I have not tried that in a while since it hasn't been working for months. I did not think about door itself being stuck I will check that today thank you. There are no spots that the AC tubing is cold no. the tubing in the engine bay is all warm or hot depending on if its high or low and the tubing in the car is warm or hot aswell. The ambient temperature was around 80-90, I couldnt tell you exact b/c I was in the shade. When the AC was off the clutch disengages, and when the ac is on it rengages. no cycle.– Big TedCommented Jun 20 at 16:52
Add a comment
|
1 Answer
Year, make, model? Many vehicles do not cycle compressors unless yours is an older r12 system. GM, for instance, uses variable displacement compressors and do not cycle on/off for r134a systems. Was this system serviced, topped off with store refill kits containing sealer? Sealer is never used in repair shops and simply contaminates systems, making it more expensive than a repair. Sealer may result in ruining a system requiring a rebuild; replacing compressor, condenser coil, receiver/drier, thermostatic expansion valve, flushing the entire system of all old oil and sealer, and seals. My personal opinion as a diyer repairing r12 and r134a systems; 98% of vehicle ac system problems are the leaks no one wants to find and repair but will run to the store for refill kits containing sealer in hopes of an easy repair to...............a leaking system. Sealer rarely works. GM r134a systems have factory dye and easily found by anyone using an inexpensive uv blacklight. Dye glows greenish yellow; removing service valve caps in GM systems should reveal refrigerant oil and dye as minute leaks occur. The valve cores can wear out and leak refrigerant, oil and dye. My initial guess is your system leaked refrigerant, about half the amount, without more info. A system with around half of specified refrigerant will create high side pressures and good low side pressures but not enough to create cold air. If this is a r134a system does it have factory dye (examine both service valves for oil and dye)? Yes, use a uv blacklight to illuminate leaks at hoses, fittings, compressor, condenser coil, etc, marked by refrigerant oil and dye.
