So I have this S90 and just replaced the orifice tube and replaced the dryer and added freon. The dryer was freezing up on the bottom when we started it back up but the air was not cold. So we're getting some compression but there is no way to check the high side pressure. This is a 1998 model. We sprayed water on the condenser while running the air to see if that was a problem but the thermometer in the vent showed no difference. Just steady temp. Any ideas on how to diagnose the compressor? Called the dealer and they said 95 bucks to diagnose it but would not tell me how he would go about doing that without a fitting to hook into. He was pretty short with me when I wanted details. I just want to know he can do it and not jerk me around and just say the compressor is bad without really being able to diagnose it. Thanks for any help.

Steve

 

What was the low pressure at?

 

Low side pulled down to 30. Thanks for any info.

Steve

 

Was that idling or reved up?
How bad was the orifice turbo you removed?
I wonder if there is a clog somewhere. 30 is a little to low on the low pressure side. The A/C should kick out at 28 PSI then cycle back on at like 50 or so.

 

I believe that was idling. The orifice wasn't too bad actually. No crud. It did have some tiny metal flakes but not many.....maybe 25 flakes smaller than pepper. Very shiny flakes. Not enough to block flow but I don't know how much metal it would take to indicate a bad compressor. We blew air through the fire wall into the evaporator both directions after we removed the dryer and blew out all kinds of oil and dye. Don't think there is a plug or restriction there. Did not try to blow through the compressor. My mechanic was pretty frustrated that there is no way to check high side pressure. He did say that he wished the low side was closer to 40 but could not tell anything without a fitting to check high side. He's a BMW guy and doesn't specialize in Volvos. Don't know if any of this info helps with your diagnosis.

 

I would make sure the condensor is not plugged.
I am fighting a 940 at work with the same problem but will not get to work on it till monday or tuesday.

 

Can I blow through the compressor to do that?

 

The more I think about it the more I think you're right about the plugging or restriction. I imagine the compressor is working since the dryer froze. Can I disconnect the lines at the orifice and the compressor and blow backwards and forewards through the condensor? Can you post a link or info where I can find a cooling diagram for this car or a similar system?

Steve

 

If you look under the car on the passenger side you will see where the 2 lines go into the condensor. Remove both of the lines and blow through the condensor and see what comes out.

 

Hey man,

Sorry for the delay and thanks for the info you've given me so far. I went on vacation and haven't been able to get back to the car until today. So I blew out the condenser and absolutely nothing came out. It didn't even vent off any pressure or freon when I disconnected it. Blew out clean dry air through both sides. Hooked it back up. Turned on the car. Compressor clutch would not engage. Went and bought some oil and freon to charge. Checked lines first and found that when the mechanic hooked up the dryer he didn't tighten down the low side fitting all the way so I have zero in the system. It all leaked out. So that's why the clutch would not engage. Charged a can of oil and a can of freon and the clutch started working but the line from the orifice to the evaporator froze up. The air in the car never got cold. One of the condensor lines is scalding hot and the other is ambient. So I'm basically back to where I started when I contacted you except that I know the condensor is clear. What could be next to try? I only charged 12 onces of freon and the one can of oil as I didn't know what the next step might be. Thanks for any more info.

Steve

 

It might be a compressor issue now. I have seen a valve go bad inside the compressor and actually pump the freon backwords which it kind of sounds like might be happening.

But there is also a possibility it is doing it from low freon. If you can take it back to the Mech and make him refill it to proper specs since he left the line loose in the first place.

 

Hey man,

I'm back again. Got the car filled to spec with freon and oil and the lines are cold like the should be. The guy that botched that job in the first place did it for free so no problems there. After scratching my head I took it to a local Volvo guy and he says the compressor is fine and that it's the controller that all the vacuum lines run to behind the glove box. He says the freon side is operating fine. Do you have any idea what the official name for this is and where I might be able to find one? I'm doing this for a friend of mine that doesn't really have the money so I'm going to try to fix it myself if I can find the part. A link to a diagram would be helpful too! I know, us internet hacks want a lot for free! But you've been most helpful so far and I've learned a lot about how air conditioning works. Thanks for any info. Oh, he said my price for the part would be $266. I paid him 35 bucks to diagnose it which I think was well spent.

 

Sorry no pics or diagrams but I can tell you what to do.
Remove the lower dash and glovebox on the passengers side. Then look on the front of the climate box and you should see like a gold square with a bunch of colored lines going to it. Unplug the lines and connector. Then remove it from the box.
Then flip it over so you can see the circuit board. Look at it closely I will bet you will find atleast one bad solder joint.

Solder the cracked joints back up and it should be good to for a while.

 

I'll give that a shot! I'll get back to you and let you know how it goes. Probably be a few days.

Steve

 

Hopefully it goes nice and smooth for you.

 

Oh yeah, do you have the official name for that part or a part number? While I'm lining up getting the car back from her I want to see what price I can get it for if I can't repair it.

 

Solenoid valve part# is 1388199