2007 xc90 A/C port reads 50 psi but not cooling

vmaxmike · Post by **vmaxmike** » 14 Apr 2015, 14:53

Was thinking AC needed a recharge as its not cooling very well lately. Typically it will take several minutes of driving before minimal cool air comes out vents if at all. Compressor is definitely running and radiator fan turns on high like it always has when system is on. I put a gauge to the low pressure port and got a reading of about 50 psi with outside temp around 85 degrees (its Miami) and system/fan running full blast. So does this reading indicate system is fully charged? Any other checks I could do before taking it in to a professional? Cabin filter looked clean by the way...
Is it possible system has lost freon but simply replaced it with air given the reading? Thanks for any thoughts on this!

Post by **jimmy57** » 14 Apr 2015, 17:52

That system uses a variable displacement compressor and the pressure is not going to conform to anything you have read around here. You will need both high and low side monitored and you will need Vida to read out the compressor variable displacement solenoid from ECM and the evap temp from CCM.
The VD solenoid can stick and is serviced as a separate part for many of the compressors and the 3.2 in 2007 XC90 I think is one that you can get.
If it was low on refrigerant and the VD solenoid was commanded for max output then the low side would run in the teens or lower. I doubt the refrigerant level is low.
What is low side pressure on initial start and what is after 30 minutes of running? Sometimes the VD solenoid is binding and once it gets hot underhood the solenoid body expands and solenoid begins to work.

vmaxmike · Post by **vmaxmike** » 16 Apr 2015, 09:37

I'll need to get someone with proper gauges as my can rig gauge from parts store may not be greatest for accuracy and I wouldn't want to try it on the high pressure side. Thanks for your reply on the other post covering the same topic which I dug up afterwards. I hope that solenoid tests ok as dealer here tells me its not sold separately. I wonder if after removing it, its worth attempting to clean the particles and reuse assuming it was sticking...

vmaxmike · Post by **vmaxmike** » 13 Jun 2015, 21:53

Finally got around to finding a VD solenoid (sold on eBay as control valve) and replacing it which did the trick!! They run about a hundred bucks but found a Chinese one w/1 yr warranty for half that and the fit was perfect and the a/c works good now. Job took half an hour. Thanks Jimmy57.

Post by **jimmy57** » 13 Jun 2015, 23:21

Great!
These solenoids stick on all makes that use them and few are serviced by the car makers.