hunter_darcy

So I evacuated the system and pulled a vacuum for 30 minutes. The system held vacuum perfectly. I added exactly 14.4 Oz of r134. My clutch kicks in just like it should. The problem I'm having is the low side is sitting anywhere from 55-70 pounds. While the high side is at 160. The ac works a little bit or it doesn't work at all.
I understand that it should be 30-45 low side and 200 high side. But for some reason tbe low side no matter what is always to high on pressure and I cannot get the highside to enough pressure. Anyone have any idea? Also the low side tends to jump up and down with throttle being pushed. The highside also jumps up and down when given throttle. 08 hhr ss

hunter_darcy

Also is the 2.0, 2.2, 2.4 all the same compressor? I'm thinking about sourcing a compressor to throw on it. I called and asked about new compressors but they are 400 bucks. But there's 10 at my salvage yard near me that I'd rather get pulled for 4 bucks.

Oldblue

1521588 is the AC compressor for the SS model , check RockAuto, they are listed around $325.00 Canadian $ new

https://www.rockauto.com/en/catalog/...ompressor,6628

firemangeorge

You should add some info if you're looking for help with the AC not working.
1. Why did you need to do an evacuate and recharge ?
2. Don't see that you added any AC oil back to the system. Why, if you did an evac ?
3. What was the original AC problem ? Any other parts replaced ?

hunter_darcy

The guy before me hit a armadillo but it jumped and went through the center of the condenser. I replaced it. Yes there is oil in the compressor. I pulled vacuum and added all the correct proportions of everything. I know fully how to do ac work. But this is the only time I've had a problem. The ac clutch works perfectly. It cycles like it should then the lowside is just pegged on 60 psi and the highside tops out at 160 or so

tiapetra

I hope you checked the orifice tube, for what little they cost it's not a bad idea to change them anyway.
I always evacuate for a lot longer than 30 minutes, unless you have a very expensive pump the vacuum will not be deep enough.
Weighing in is the proper way for most systems, but I much prefer to watch the gauges and stop at around 35 depending on the temps of course.

From the pressures and the temps you stated, it would indicate there is an overcharge.
I would capture the refrigerant and start over.

And you can get brand new compressors for as little as $120.00 on ebay and Amazon, if you feel the need, I would not do rebuilt.

hunter_darcy

It isn't overcharged. I literally used a scale and put in 14.4 Oz exactly. There is 0 leaks, the compressor has oil, the condenser is new, the pressure cycles fine until I had about 11 Oz of refrigerant pumped in. As I added the last 3 Oz it only made the low side rise. The highside will not raise above 125.

I have recharged 20 or 30 ac systems. I understand how to do it. I understand the amounts.

All I need to know is what would cause the lowside and high side pressure to flow and act normal until the last 3 or 4 oz of refrigerant. Upon that moment it all seemed as If it went only to the lowside and would not pass anymore to the high side.

donbrew

You didn't address the orifice tube.

tiapetra

I answered that as best I could, including a compressor as a last resort.
Seems you have it under control.
Good luck.