replaced my dccv.. and ac stopped working again

zzmontyzz89 said:
this was with car running a/c on at 85-87 degrees Fahrenheit outside temp.
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That was with the blower on high, I assume. The pressures (particularly the low side) are a little high, but acceptable.

Are you sure that the engine cooling fan is running fast enough? Is the condenser clean and not to bent up?

You might try pinching the heater hoses completely closed and see if that changes things.
 
Yes the fan was on the highest setting. I tried with the ac on and recirculate, and without recirculate. Also tried the auto setting with temp set at 60 still and fan on high. What I did notice. The compressor was not cycling. The low side didn't move at all when the ac was on. So does that mean the compressoris bad? And iif that's bad how could I still get 1 side cold and the other side warm. And when its cool outside the driver and passenger blow pretty nice but not as cold as it should be of course. I don't know where condesor is located. The engine fan seems to be blowing just fine. And when you say heater hoses you mean the 3 hoses plugged into the dccv?
 
The AC compressor on the LS is not supposed to cycle most of the time. It is a variable displacement system with a thermal expansion valve. This means the compressor can run at different rates, so it doesn't have to cycle on and off to maintain the correct pressures. It will cycle off if the cooling demand gets so low that the evaporator starts to freeze up. There is a temperature sensor to read this. There is no low side pressure sensor like most systems have. There is only a high side pressure sensor. It will shut the AC off if the pressure goes too high, and it will prevent it from ever starting if the [high side] pressure is too low.

It's possible that the compressor is bad. They have been known to fail such that they no longer pump enough refrigerant. However, normally when that happens, your high side pressure would be a lot lower than you have. You would also probably be reporting that it cooled much better at highway speeds than at idle.

The condenser is in front of the radiator. The transmission cooler is between the condenser and the radiator. (Just to be clear that the condenser is the big thing behind the grill.)

When you start the car cold with the AC off, the fan should turn slowly. If you then turn the AC on, the fan should speed up greatly.

I mean the three hoses that run back to the heater cores. You only really need to pinch off the return hose, but if you are not sure you are completely blocking that hose, it might be better to do all three.
 
Ok after work ill check the condensor for problems. And ill check the fan and see what's going on with that. Thanks for everything man ill post soon.
 
Ok so the fan speed is doing what its supposed to. But I did notice after I pulled the cold side hose off the ac line it started to slowly leak out from the tip of it. I out my finger on the tip and Ill have freon on it. What's that mean?.
 
zzmontyzz89 said:
Ok so the fan speed is doing what its supposed to. But I did notice after I pulled the cold side hose off the ac line it started to slowly leak out from the tip of it. I out my finger on the tip and Ill have freon on it. What's that mean?.
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It's not too uncommon for the Schrader valves in the fill ports to start leaking. The valve cores are replaceable (even with the system still charged with refrigerant - just takes a special tool and a lot of care). The dust cap that goes over the fill port has an o-ring to try and keep a small leak from being a problem.

BTW, R-134a refrigerant is not "Freon." It's "Suva."
 
Ohhh ok cool well I lost the cap lol. So ill clamp the hoses and see if that changes anything. If it makes my ac cold what does that tell you?
 
Yeh on a cold start the only thing that changes is the passenger side will blow somewhat cooler air thenit normally does. Also at ccooler temperatures outside it blows just a bit cooler. Not much at all. But the rear vents are blowing warm air constantly
 
Alright Idk where some of my messages went. But ill say it again. I checked the fan its ok. Their was a hose that I forgot to clamp all the way it was leaking slowly. I clamped it and cleaned all electrical connections and plugged them in all the way. Refilled coolant and proceeded with bleeding the system properly. After that I tested the ac and still no change. Their has to be a clog somewhere either in the orifice tube if the ls has one or my evaporator?
 
zzmontyzz89 said:
... Their has to be a clog somewhere either in the orifice tube if the ls has one or my evaporator?
Click to expand...

There is no fixed orifice tube. The LS uses a thermal expansion valve in combination with a variable displacement compressor.

A clogged valve should result in a higher pressure reading than you were getting on the high side.
 
Back the when you said clamp the Hester hoses and see. Whenever its cooler outside and I start it cold. The air blows pretty nice but the passenger side is never as cold as the drivers side.
 
Well, I do think you might be better off at this point to take it to a professional.

There really isn't anything more to be done to check the compressor and the expansion valve other than to replace them. A professional with experience with this system may be able to make a good guess by watching the gauges as he revs the engine and adjusts airflow.

The gauges show refrigerant pressures, not levels. Yes, you normally get a really good guess at the levels knowing the pressures and temperatures, but that is only true if everything is working the way it is supposed to. Yours is not, so the pressures don't really tell you the levels. Anyway, I was more thinking that you may have too much contamination (oil, air, leakstop, ...) in the system, making the R-134a level percentage be too low.

The pressures indicated do not suggest a leak being the problem.
 
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