jrod954

I have a 1993 Corvette and the A/C only blows hot air! The fan works, but when the auto button is pushed only hot air blows. My A/C worked fine all summer long including just two weeks ago! What laundry list should I check to make sure it's not electrical problem, compressor problem, or freon problem?

Any ideas. I can check pressure and freon using gauge from AutoZone!

Thanks,

Iroc57

Since you said hot and not warm check your controls and not the system itself. The system is probably being told that your inside temp is way low.

Just a thought

jrod954

I set the temp to the lowest setting - 60 and the inside temp is 79. Same result - hot air!!

Sparkostatic

Do you hear the Cold Air door closing/switching?Mine was stuck...Had to help it close all the way.

jrod954

No - I don't hear it switching... where would i find it to push manually?

Sparkostatic

Im pretty sure your car uses the same parts but here is a pic.Remove the 3 or 4 screws holding the switch/rheostat down.Once you open it up dont force the door hard,you will feel resistance.Just help it close.You will see what Im talking about..Hope this helps..Do this with the car running(Vacuum)After the switch is removed(Sorry if I named the part wrong!!!)

desertmike1

Is your compressor running/cycling, if so is the large aluminum (compressor suction pipe) cold to the touch. If the compressor is running, and the return (suction pipe) is cold then the problem is in the air box or controls.

If the suction line feels cool, not cold, or warm then the problem lies in the compressor or related equipment. This could be a simple low charge, but in order to properly trouble-shoot, you would need a set of air conditioning gauge's, and check the system High side/low side pressure's.

Sparkostatic

Thanks desertmike1 for also stating compressor related problems!!!

Sparkostatic

There is a thread in the tech section right now that shows more detailed pics on this problem .Check it out...

fishchris36

when my c4's ac was blowing cold my l-98 temp would clime and not stop. why is that?

Chris
http://www.continentalautotransport.net/

Sparkostatic

You probably had a 180-190 thermostat plus the load on the motor.A 160 degree would have solved that.Your also in Florida...Correct?

gary 53

thats it

LannyL81

I think the '93 is the same as my '95: there is a small electric motor that moves the temp door. Located above passenger foot well. Couple of screws and a small electrical connector. Drop it off and move the door by hand to make sure it moves. With the motor hanging and still connected electrically, set the temp to full cold or hot and see if the motor moves. If so, then you will have to move the door by hand to align the motor shaft once again to reinstall. This way you know that the temp door is moving.

I had a cold solder joint on the motor and a few seconds with a soldering iron it was operating once again. Here is a photo of the unit with the cover off.

jrod954

I need to add freon to the system and want to double check that I am correct on the location of high and low pressure. Would someone take a picture of the high and low pressure for me? And should I add the freon to the high pressure?

jrod954

I found the leak today!! I added a can of freon and heard a hissing noise from the front of the car. I noticed a major leak from the bottom of the condensor (condensation was puddling in front of the radiator). The compressor kicked on for a few minutes so it is good. How difficult is it to replace the condensor? Should I replace any other part of the A/C system as well? Any suggestions would help!

Thanks!

jsdomino

You really should have the whole system purged, replace the condensor, inspect the other parts. Then have the system recharged. You will need guages and a vacuum pump, or just replace the parts then bring to an A/C shop. Your '93 should use R-12.

You may wish to have the system converted to R-134, but that is your choice.

desertmike1

Bummer about the Condensor! maybe a rock strike.. Look at your Air Conditioning label under the hood, either on top of the Radiator air box, or at the Heater/A coil air box, this will tell you which Freon your car use's R12/R134A. 134 would be a good thing!!
A/C Condensor coil is very easy to replace, disconnect the tubing, slide a sandwich bag over the tube ends, and tape off to keep the system clean, Remove the upper air box cover, and slide the coil out. Replace the Condensor coil, what you will be doing next is based on what Freon your system use's.

jrod954

It uses R12...

Goldcylon

Hmm Maybe Arctic12 is the way to go at this point. You will need to retrofit the Inlet valves so the R134 Fittings will adapt and replace the compressor otherwise in order to do a true R134 conversion.

At this point I would use the drop in R-12 replacement. IMHO

jrod954

GM Dealership suggested that I convert to R134. For $465 they will replace the valves (hi/lo), evacuate, pressure test, and fill the system with R134. Does this sound correct?