Working on an '07 Civic LX sedan, auto. No cooling from AC. Static pressure is 125 PSI (it's hot out). When the clutch engages, the compressor sounds fine, no ugly noises. The low side pressure drops to like 110-115 PSI, and the high side pressure drops slightly as well. Before deciding the expansion valve is bad, anything I should consider / try? Thanks!

 

That sounds more like the compressor has no compression left.

 

Thanks! How would I go about verifying that?

 

Clamp off a rubber AC line and see if anything changes.

Be mindful of where you are reading pressure in relationship to where you are clamping. You will see a pressure increase or decrease depending on where you clamped.

 

Great idea, thanks. I clamped the hose all the way down while the compressor was spinning, had no impact on pressures. Guess that does it for the compressor.

 

Bummer. At least you didn't have to unload the parts cannon on it.

Be sure to inspect for the black death. A compressor with no compression is a great source of black death from all the debris involved with a compressor failure. But maybe you got lucky and it is something simple like a stuck or broken valve that doesn't spray shrapnel into the system.

 

Yeah, totally. Given the lack of nasty noises, even with a stethoscope, I'm optimistic. It hasn't been driven much since it stopped compressing, so fingers crossed.

 

Alas, the black death is upon him. Finally got the new compressor and condenser, opened the system, and found this in the old compressor. I pulled the evaporator, ordering evaporator and expansion valve now.

Can the lines be flushed, or should I replace them too?

 

Ouch. I have flushed AC lines and evap cores in the past out of the vehicle with acetone. In changing from R12 to R134a to get the incompatible oil out. I didn't have any issues.

 

Thanks, ordered a flush kit for the lines. Both sides of the expansion valve are full of junk, no way am I reusing that evaporator.