2008 Impala Compresssor

[U118224]

2008 Impala, AC quit working. Equalized pressure at 115-120 at 75-80 degrees ambient. When diagnosing I turned the AC on - clutch engaged but the pressures didn't change, they stayed equalized. The compressor makes a squeaking noise at startup and shutdown, otherwise is quiet. My guess is that something broke in the compressor that didn't affect the refrigerant "side" of the system. This car has 286,000 miles and is in good shape, but I'm not inclined to spend $500 in parts to replace the condenser and expansion valve as well.

Based on my symptoms, the age and mileage of the car, my inclination is to just replace the compressor. I know that's not recommended but I am looking for opinions. Thank you!

[bohica2xo]

That vehicle has a variable displacement compressor. Recover the charge & weigh it - probably not much left.

A new AC Delco condenser is under 150 bucks with a new dryer if you need one. TXV about 60 bucks.

Could be you just need a new control valve in the compressor, or just a fully charged system.

[U118224]

Bohica I appreciate the reply, but I don’t believe it’s low on refrigerant. Static pressure is 115 psi on both the high and low side at 80 degrees F. That doesn’t seem low to me. Anyway, when I replace the compressor I’ll measure the charge. The dryer is ntegral to the condenser and is not serviceable.

[bohica2xo]

We,, as GMTech used to say

The number one A/C diagnostic tool there is- is to know how much refrigerant is in the system- this can only be done by recovering and weighing the refrigerant!!
Just a thought.... 65% of A/C failures in my 3200 car diagnostic database (GM vehicles) are due to loss of refrigerant due to a leak......

Suit yourself.