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Tim Mohr
Tim Mohr, ASE MASTER TECH
Category: Cadillac
Satisfied Customers: 15154
Experience:  30 YRS EXPERIENCE, FOREIGN AND DOMESTIC, GAS AND DEISEL
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Cadillac Eldorado: Our 1997 Eldorado blows hot air from AC

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Our 1997 Eldorado blows hot air from AC vents.
We have checked freon pressure is good, compressor is turning on, mixing arm moves when AC I s activated, fuse and relay are good... We just purchased the car and don't know any history.. Any ideas???
Oh also the evaporator and lines are hot to the touch.
Hi, my nname is XXXXX XXXXX was the actual high and low side pressures when the compressor is running?
Customer: replied 3 years ago.
I used a gauge that came with the can of refridgent it was in the green section(good) I think 180??? I did not add more.
180 is too high for the low side pressure, how much did you add?
Customer: replied 3 years ago.
I did not add any !!
As soon as I hooked up the gauge (larger tube) the gauge went to green indicating good pressure) it was right in the middle of yellow(low) and red (high) I can't recall the actual pressure reading.
if it was in the green area, and the compressor was on, then its full, if both the tubes going through the firewall were hot, then you have a bad orrice tube in the system, but to verify this, you would need a set of gauges to put on the high and low sides, but if its full and running, then you have a bad orifice tube and it will need to be replaced,Tim
Customer: replied 3 years ago.
Assume it's the orriface
Where is it? What does it look like?
the orifice tube is located inside the low side line, near the furewall and the low side connector, you must remove the coupler and seperate the lines, then use a pair of needle nose pliers to remove the orifice tube, the orifice tube cost about 8 dollars at most parts houses, the system will need to be drained before removing the coupler, and it will need to be evaced and recharged when done,Tim
Tim Mohr and other Cadillac Specialists are ready to help you
the orifice tube is located inside the low side line, near the furewall and the low side connector, you must remove the coupler and seperate the lines, then use a pair of needle nose pliers to remove the orifice tube, the orifice tube cost about 8 dollars at most parts houses, the system will need to be drained before removing the coupler, and it will need to be evaced and recharged when done,Tim




Customer: replied 3 years ago.
Hi Tim
We replaced the orifice tube (the old one was packed with black guck)
We recharged the system and have the exact same symptom.
Pressure is correct, compressor comes on, still blows hot air.
Any ideas???
if the old orifice was plugged with debris, then the system needs to be flushed, did you put a set of gauges on it, and read the actual high and low side pressures, or just the gauge that came with the refrigerant?
Customer: replied 3 years ago.
Just the gauge that came with the refridgent ... The orifice tube was real bad!
How do I flush it?
most parts houses sell a kit for flushing it, it consists of chemicals and spray can, you remove the lines off the compressor, the orifice tube, and the accumaltor, then spray the chemicals into the lines and through the condensor and eveaporator, then let it nsit for an hour, then use compressed air to bow out the lines, but if there was a lot of black material in the orifice, this is usually caused by the compressor failing, this is clutch materiak from the compressor, so it might be best to replace the compressor, but you can try flushing it first, have you removed the orifice again and seen if its plugged up again?
Customer: replied 3 years ago.
I'll try flushing it
But I'm starting to think the compressor is bad.
it can be, if there was alot of black debris, but you will need a set of gauges to monitor the high and low sides, the low side should be around 35 psi when the compressor is running, and about 150 to 200psi on the high side, but that debris had to come from somewhere, and the compressor is the likely culprit,Tim
Customer: replied 3 years ago.
We checked the new orifice tube and it was clean.
We did notice that after letting the pressure out to work on it and then refilling it.. It only takes a few oz to fill.
The specs say it holds 2lbs.
Yes, it h2 lbs, you need to fill it with 2 lbs, have you done this yet?
Customer: replied 3 years ago.
No not able to add 2lbs.
As soon as we put a couple oz in the gauge says full . also the compressor does kick on. All tubes and condenser are hot to the touch.
Did you put the system into a vacuum for an hour before recharging it?
Customer: replied 3 years ago.
No
We just used the off the shelf can and gauge.
The air has to be evacuated out of the system before it can be charged, this is done with a vacuum pump, and a set of gauges, most parts houses will loan you the gauges d=foe a small deposit, these gauges are eseential to diagnose the system, can you get a set?