A/C Issues - Completely lost at where to look next

[Ghh0st]

I'm having an issue with my 04's SE's A/C. Here's what I've checked/ran through so far:

-Condenser is clean and clear
-When having A/C on at full blast, the compressor kicks on as it should but blows hot/outside temp air.
-Cabin Air Filter is brand new and clean
-System is charged to the right pressure (after I refilled it with a can from the auto store)

-I get heated air no problem from the car when changing the temp controls to hot, just no A/C.

I'm at a loss at where to look/ what troubleshoot next. Any help would be greatly appreciated.

Thanks!

[RJolly87]

Are cooling fans winding up behind the radiator, and are both lines going to the evaporator cold?

[Ghh0st]

Are cooling fans winding up behind the radiator, and are both lines going to the evaporator cold?

Are cooling fans winding up behind the radiator - sometimes, but not always when I turn the AC on.

Are both lines going to the evaporator cold? - I don't believe so.

[Ghh0st]

I also noticed yesterday that in the engine bay fuse box, there's a spot for a HVAC relay (#39 I believe) and it has no relay in it, would that cause the issue I'm seeing?

[nos4blood70]

No relay could definitely be the cause. If I'm not mistaken, the relays are all the same. So you can swap one out from something else to see if it works, or purchase a new one at Autozone or something for a couple bucks.

[Ghh0st]

I went to swap one in and the relay just floats around in the slots. So there isn't an HVAC solenoid relay there. And for reference that relay slot is actually #33.

[Ghh0st]

I also had to change the AC orifice in the line, does that mean I have to have the system professionally vacuumed and recharged? Trying the recharge canisters hasn't helped my situation after changing the orifice.

[RJolly87]

What pressures were you seeing in the A/C Before and after you charged it, on the high and low side. And also, was the compressor running before the refrigerant went in, or did it start only after the can went in?

[Ghh0st]

What pressures were you seeing in the A/C Before and after you charged it, on the high and low side. And also, was the compressor running before the refrigerant went in, or did it start only after the can went in?

I don't have a full A/C Pressure gauge, just the ones that come with the can you buy at the store. The reason we changed the orifice was because it wasn't holding any pressure on the low side, it would just continue to build and not hold the pressure at a consistent value (now after changing the orifice it does hold pressure). Initially, when I first checked the low-side it was 100 (before changing the orifice). After changing the orifice we charged it (using the bottle from the store).

And the compressor did not start to turn on until after we started adding refrigerant.

[RJolly87]

Was the compressor engaged and turning when you were getting the 100psi reading before changing the orifice?

[RJolly87]

From the information I am understanding, I am concerned you don't have the knowledge and understanding necessary to be safely working with the A/C, and think it should be taken care of by someone who does.

However, I will share the following information.

Any time the A/C system is cracked open, like when you are changing the orifice, it should be fully evacuated, and have a vacuum pulled, usually for about 30 min. This allows moisture to boil out of the drier, and also confirms there are no leaks in the system. Also, it's important to ensure enough oil is in the system.

Now, here is the bit that is probably affecting you. Your Bonneville uses a variable displacement compressor. This means it can adjust the compressor pitch, which can ramp up or back down the system pressures to keep them where they belong. The down side to that is that is that the pressures can still appear to be fine or close, when in reality, there is not nearly enough refrigerant in the system. Your system takes 35 oz of refrigerant according to this chart: http://www.techchoiceparts.com/refriger ... op#pontiac

The typical R-134a can is 12oz, so it takes 1 oz shy of 3 of them to get a proper charge in the system. Given the system was completely empty (compressor not kicking over) when you put the can in, you probably need to add another 2 cans worth.

And that's assuming there is not another issue. A full gauge set is a must if you plan to fiddle with your own A/C system in the future, as well as reading up on how the A/C system works. Too much can be going wrong, and you can't see it if you are only looking at low side pressures.

[Ghh0st]

From the information I am understanding, I am concerned you don't have the knowledge and understanding necessary to be safely working with the A/C, and think it should be taken care of by someone who does.

However, I will share the following information.

Any time the A/C system is cracked open, like when you are changing the orifice, it should be fully evacuated, and have a vacuum pulled, usually for about 30 min. This allows moisture to boil out of the drier, and also confirms there are no leaks in the system. Also, it's important to ensure enough oil is in the system.

Now, here is the bit that is probably affecting you. Your Bonneville uses a variable displacement compressor. This means it can adjust the compressor pitch, which can ramp up or back down the system pressures to keep them where they belong. The down side to that is that is that the pressures can still appear to be fine or close, when in reality, there is not nearly enough refrigerant in the system. Your system takes 35 oz of refrigerant according to this chart: http://www.techchoiceparts.com/refriger ... op#pontiac

The typical R-134a can is 12oz, so it takes 1 oz shy of 3 of them to get a proper charge in the system. Given the system was completely empty (compressor not kicking over) when you put the can in, you probably need to add another 2 cans worth.

And that's assuming there is not another issue. A full gauge set is a must if you plan to fiddle with your own A/C system in the future, as well as reading up on how the A/C system works. Too much can be going wrong, and you can't see it if you are only looking at low side pressures.

Thanks for this, my inspection is due in July so I'm going to have it evacuated and recharged by my local trusted shop. My dad had told me that it should be vacuumed but to try adding refrigerant first to see if that helps. I've fixed a few other things and this is the last to-do on my list. Once I get the car to the shop I'll write back if the evacuated/recharge helped or if it was something else.

Thanks again.