A/C Compressor Question
 

Having A/C problems. When the weather is cooler in the evenings the a/c air temp is good and cold. When the weather is hotter during the day the air temp is just slightly cool almonst warm. The system is full of freon. Do I have a compressor going out, if so would a compressor rebuild kit solve this problem? Haven't rebuilt one before but I think the only thing supplied in the a/c compressor rebuild kits are paper gaskets and rubber o rings. Do I have another problem? Thanks

Do you hear a "click" when you turn the Temp Control knob?

I am no expert on compressors but....

My understanding is that they either work or simply fail. Mine have usually had a seal failure due to age. I have never personally had one wear out and not compress.

Check to see if the clutch is on most of the time. Maybe it's cycling on infrequently. Have you put a set of gauges on it? I wouldn't jump to a compressor problem just yet. The Nippodenso compressor is often rebuilt to replace the nose seal which wears out and leaks. Look for a pattern of oil on the underside of the engine lid. Lot of guys have just replaced it with a Sanden. That's what i would do if the thing was totally shot.

could be a variety of things. poor condenser performance will be noticeable in the heat, poor evap performance... same. bad temp switch could provide an illusion of cold but not really be cold (have you measured actual air temps)? I too doubt it is the compressor.

Was it properly evacuated before being filled? Too much refrigerant will cause the system to not cool (not to mention high pressures will blow seals and even the compressor).
If 134a is in there, was the system flushed and 134a compatible compressor oil put in?
Did you replace your receiver drier? (moisture will cause under-performance).

Yes the compressor clutch is engaging so I know this much. I'll check some of the other things that were mentioned as well and get back. Thanks.

you need AC manifold gauges hooked up to the compressor to know the high and low side pressures and diagnose it. without them you're only guessing and wasting time.

harbor freight tools has a decent and inexpensive set more than good enough for home use. they go on sale for around $50 sometimes.

Autozone has a nice set for $55. Made in the USA.

good to know...

Autozone is also sells bosch the wideband oxygen sensor #17014 for less than anywhere else including amazon.com.
It's made for VW's and it's the same one used with Innovate widband AFR gauge controllers and kits.