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99 grand prix AC problems


ladytaralynn
10-26-2010, 01:43 PM
:banghead:I have spent so much money trying to fix my AC system in my 99 Grand Prix. I have bought the gauges, the pump several cans of freon, a new condensor, a new accumelator, new AC lines, New Compressor everything but even when using the pump and leaving it running for a hour or more at a time I try to put the freon back in but I still do not have AC in my car. I have the GM books Mr Goodrich uses to fix cars so I knew what all needed to be replaced. Now I am down to the heater core behind the dash which is going to take me several hours to pull apart and change out. I found a heater core at a junk yard and spent $50 dollars on it. On the outside it doesn't look bad but Was wondering if there is a way to pressure test this to make sure it is good? What am I doing wrong and why can't I get AC in my car. It seems to suck out all the air when I put the pump on it but then it is like it stops pumping. I assume there is a restriction but I dont know where it is. Everything is brand new. I have just about replaced everything on this car from the engine, to plugs and wires, most of the sensors. I am at a loss now as to what I need to do. Can anyone help me?:disappoin

olopezm
10-26-2010, 04:23 PM
As far as I know the heater core has nothing to do with air conditioning and freon, the heater core is for heating the air, not cooling it and the only thing that goes through it is engine coolant, nothing else. I'm sorry that I cannot help any further, but it would suck if you buy the heater core only to find out it made no difference at all. That's my two cents.

Best regards,

Oscar.

doctorhrdware
10-26-2010, 05:54 PM
Ok, are you able to charge the system with freon, if you are, then does the ac compressor turn on. If it does then I am wondering if there is a problem with the doors that control the air flow, that select ac or heat. If the door is stuck in the heat mode then you would not get the cold air into the car. Also what is the reading on the gage in other words how may inches of vacuum are you pulling the system down too.

tblake
10-27-2010, 01:53 AM
Maybe you mean Evaporator Core instead of Heater Core? The Evaporator Core is a BIG job to replace as just a guess. Is the condensor in front of your radiator clear of dirt and dibris? Do your coolin fans turn on when you turn your AC on? Is this a SE, GT, or GTP, or do you have automatic digital HVAC unit or manual?

doctorhrdware
10-28-2010, 01:54 AM
Good catch Tim, I just reread the op and the evap was not replaced. I guess I had a brain fart again.

tblake
10-28-2010, 06:13 PM
No prob. We all have brain farts from time to time. Me more that most at times.

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