No brakes in the morning. It will definitely wake you up more than coffee.

[jamesd]

It's an automatic and the a/c does take a while for it to cool down. After a while like at night time it gets to 50F coming out of the vent.

[WyrTwister]

Do you have guages ?

God bless
Wyr
:

[jamesd]

I sure do! On Saturday I had put dye in the a/c system and found a leak using UV light. Leak is where the a/c lines connect to the compressor.

[WyrTwister]

Is it a bolted system . If so CAREFULLY try tighten it . If it does not tighten , you may have to replace the O-Rings or sealing washers , after the system no longer contains refrigerant . But when you open the system , do so quickly , put it back together then use a vacuum pump to evacuate it to a hard vacuum , I would run the pump for a couple of hours . Shut it down and valve off the gauges . Let it sit for another hour or two & see if you loose vacuum . If you do , you still have a leak .

No leak , charge it by weight with refrigerant . ( Probably R134a . ) Should be a sticker under the hood that tells how many ounces it holds .

If I can be of assistance , email me off list - WyrTwister@hotmail.com .

What about the other engine codes , did they show up again ?

God bless
Wyr

[WyrTwister]

Or , if it is a slow enough leak , you may be able to top it off with some refrigerant . Pay close attention to your pressures . Walmart had cans of R134a , locally for ~ $ 5 a can .

I use a 25 pound jug . I bought when it was about $ 10 for the 12 ounce cans .

And , yes , I have an EPA card for automotive A/C and the 1st level card for smaller A/C systems .

If you do not have a vacuum pump , " borrow " one from your local AutoZone , O'Reilly or Advance Auto Supply .

God bless
Wyr

[WyrTwister]

Does the hose end , that attaches to the compressor , look like this pic ? If you open the system , replace the O-Rings with ones rated for A/C - refrigeration and coat them with refrigeration oil or Nylog Blue .

God bless
Wyr

[jamesd]

Wow thanks for the tips!!! This is all awesome information! Thanks!!! I don't have a vacuum pump but I may go with renting one from Autozone. As for the codes I took it back to the dealership to check it out and this is what they wrote on the repair order, "CHECK AND DIAGNOSE LOW IDLE CODE RE LEARN IDLE AND ADJUST IDLE CLEAR CODE TEST DRIVE VEH WORKING TO SPECT."
So they did a relearn I guess. I imagine that should have been done when they replaced the throttle body. We will see what happens later as, "The Aveo Diaries" mini series continues lol.. Oh and yes the connection looks just like that.

[WyrTwister]

Sounds like things are getting better .

You can find a lot of good info on A/C repairs on youtube .

One thing , there is a product called Super-Seal . Or something like that . I have read a LOT of negative things about it . I would not risk putting it in a car or an air conditioning system for a home .

Anytime you hook up hoses to an A/C or refrigeration system , purge the sir out if the hoses and manifold / gauges . Moisture is the enemy of A/C or refrigeration . And air ( containing moisture ) . The refrigeration oil will absorb moisture . The synthetic oil used with the newer refrigerants is worse to absorb moisture than the mineral oil used with R12 & r22 .

Anytime you have a system open to the air , very long , it is important to replace the Accumulator dryer / receiver dryer .

And vacuum down then system to a hard vacuum . This will help remove the moisture , along with the air .

You will normally get the best performance from the system if you charge it with the number of ounces of refrigerant the documentation calls for . More is not better .

God bless
Wyr

[WyrTwister]

By the way , experience is what you got when you did not get what you wanted .


Honestly , on the Aveo A/C , if it were mine , I would try to tighten the fastener holding the hose to the compressor . And if the leak is minor , I would top it off with R134a .

Put a thermometer in the vent / grill in the dash . With the A/C set for full blast , slowly start adding a little refrigerant and the air discharge temp should slowly start to come down . Rev the engine to 1500 - 2000 RPM . Hopefully , you will get to 50F or lower .

At the same time , watch the low side pressure on the low side gauge .

You may or may not know this , but refrigeration & A/C , comes down to temperatures & pressures . In the most basic sense .

Here is a temperature pressure chart for R134a .

https://www.google.com/url?sa=t&rct=...01I3vw&cad=rja

If you look at the chart , 32 F corresponds to 27.8 PSI . That is the pressure that R134a boils at , in a perfect situation .

You do not want the evaporator coil to get that cold . You are in danger of freezing the coil . That blocks air flow and things will go from bad to worse .

I personally like the pressure to be at 30 - 35 PSI , which corresponds to 35 f - 40 F .

And the temp of the cold gas returning to the accumulator or the compressor needs to be high enough that all the refrigerant is vapor / gas , by the time it gets to the compressor .

You do not want any liquid refrigerant making its way back to the compressor . Liquid does not compress very well and can damage the compressor .

So monitor the air temp at the grill / vent & the low side pressure .

Too much refrigerant raises the pressure & thus the temperature and if does not get as cold & does not cool as well .

God bless
Wyr

PS The difference between the temperature of the low side hose / pipe , before it enters the compressor & the temperature you get from the chart ( when you cross reference it to the low side pressure ) , saturation temperature , is called super heat ( subtract the 2 temperatures ) . The optimum value for super heat varies form one A/C / refrigeration system to the next . But the returning vapor needs to be warm enough to assure no liquid refrigerant enters the low side / suction side of the compressor .

The number of degrees of super hear is heat absorbed , by the evaporator coil , from the cabin air blowing through it . And any heat picked uo in the hoses / piping as the refrigerant travels from the outlet of the evaporator coil to the compressor .

[WyrTwister]

Forgot to mention , the pressures are affected by the temperature of the outside air ( especially the high side pressure ) and the cabin air ( especially the low side pressure ) . And both are affected by engine RPM and the flow of outside air through the condenser coil ( in front of the radiator ) and the radiator fans .

If you are topping off the existing refrigerant charge , in your drive way , you may need to run an extension cord outside & place an electric box fan blowing on the nose of the car / radiator , to simulate the air which is normally forced / rammed through the radiator , as you drive down the road . It is not really so much the radiator , but the condenser coil is normally positioned next to the radiator / in front of the radiator .

The condenser coil is the part that you are really concerned about , when you are working on the A/C . If you have one or two electric radiator fans , all ( 1 or 2 ) of them are normally forced on when you turn on the A/C , to increase air flow through the radiator and condenser coil .

All this is why the most accurate way to charge the A/C is to vacuum the system to a hard vacuum then weigh the amount of refrigerant added . To the amount specified for the car .

God bless
Wyr