A/C Compressor Troubleshooting

[sahls01gmc]

Well, I wanted to post a follow up on this in case anyone in the future finds this article. After hooking the truck up to an actual A/C machine, I took all of the R-134 out of the system and did a vacuum test. It passed the test, holding 30lbs of vacuum for 30 minutes. Upon trying to charge the system, I was only able to put about .2 lbs. of R-134 into the system. I tried on both the high and low side, and didn't have any luck. So, by that point I had determined that the compressor was the issue. I took the R-134 back out and headed to O'reilly's....

 

After taking the old compressor off, I did flush the system with twice to get any other contaminants out. I added oil to both the new dryer that was already installed as well as the new compressor. I also replaced the gaskets on the lines connecting to the compressor for best hopes of no more leaks. After putting it all back together, I stated it up and began to add R-134 again. This time, I was able to put almost 2lbs in the system. Finally, the cold air started working again!!! I fixed it on July 4th, and have drove almost 600 miles since then, and it is still ICE COLD!

 

 

Thank you for all of your help. I learned a bunch along the way, and got working A/C in the end. All is well.

 

 

Here's a tip for anyone with the A/C compressor located on the passenger side under the water pump. I used the Chilton's manual to get my feet wet, but found a much easier way to get the compressor out:

 

- Take off the plastic "skid plate" air deflector on the front of the truck with the 5 15mm bolts

- Take off the 4 15mm bolts holding the metal skid plate under the oil pan

- Remove the A/C belt from the compressor, and unbolt the tensioner from the engine (provides the necessary clearance)

- Use a variety of 15mm sockets and accessories to remove the 4 bolts holding on the compressor to the bracket. I ended up using a short and long 15mm (3/8"), 3", 6", 12" extensions, and swivels as well. Space is kinda tight

- Remove the 15mm bolt connecting the lines to the compressor

- Dont forget to unplug the high pressure switch on the back of the compressor (It's hidden under the compressor lines when installed)

- After all bolts are out, and both sensors are unplugged, take the compressor out towards the radiator and drop between the transmission cooler lines and A/C condensor lines. Moves in and out really quickly through there. Won't come out that way unless you remove the A/C belt tensioner though!

 

If anyone else has any further questions, feel free to ask.