So I just bought this absolutely stunning white 93 Z28. Its really the car of my dreams. I remember when my family moved to Florida in 94, my dad bought me this camaro model kit and it was LOVE at first sight. I have been obsessed ever since.

So fast forward to last Monday. I finally find one that tickles my fancy and I get my wonderful father to help me bring it home(1.5 hours away). All seems well.. car runs great, all the features I want, mileage a little high(115k) but its 20 year old car so what can you do?

I notice after I get it registered and insured that.. the ice cold AC seems to just go out whenever I go over 35-40 mph. Now when you turn AC off, then turn the car off, and then turn it back on.. it works fine.. until you go over 35-40(this isnt an exact number but generally in this range). Just turning the AC off then on with the car running doesnt make it work. Turning the AC off, then restarting the car does.

I am absolutely perplexed by this issue. Have any of you ever heard of something like this? I am not the most mechanical person but I am learning alot. Ive got a 2002 3800 series that I am in the process of doing the head gasket job on in my spare time and this is really the first time Ive ever really done anything of this magnitude but I am actually having a great time fixing it up. I hope to someday be able to do the majority of my own repairs(aside from automatic transmissions.. WOW what a complex piece of machinery).. and Id love it if anyone could shed some light on what might be causing this. Thanks in advance

 

being i dont know much about ac i would take it to have the ac serviced. it may just need recharged, i tried that once, lol. didn't have much luck. good first step is a factory service/shop manual. 93 books are not to expensive http://www.ebay.com/itm/1993-Chevrol...830d19&vxp=mtr or can download one here. https://www.mediafire.com/?40mfgeoe4ctti 93firebird should be good for you.

 

I have one.. Paid 30 bucks for it only to find a few download links after the fact lol. Anyways the ac is ice cold when it's working. And the fact that it works but then fails makes me think it's maybe either an electrical issue or some kind of pressure issue. Thought maybe someone might have had a similar problem with a relatively easy fix :P but of course it is never easy lol

 

HVAC may need some gas, er, R134.
You can get the kit with a can of R134 and a gun with a gauge, hose, and quick disconnect, try Wally Mart.

The kit plugs into the suction side and the gauge shows pressure of suction side.
Normally, around 32-36 lbs should be good, read up. Your manual will tell you.

If you can, leave gun hooked up and go for a drive.
When A/C goes out, lift hood and view gauge.
If low, add more gas, bring it up to previous reading.
If low pressure, evaporator has iced up and no cold air.
If adding gas over a short time, say a week/month, look for a leak with Snoop - can be bought at any A/C place.

 

Ive heard that it can be risky to do this as I could potentially damage the compressor, is this true? Also I checked my trouble codes and getting DTC 61, AC system performance, basically PCM determines refrigerant charge below predetermined level. So it would seem that you are correct.. I just want to make sure its something even an idiot like me can do without wreaking havoc on the systems in the car :P and even if it is risky.. that I do it as safely and properly as I can.

 

Buy a kit and read instructions supplied.
Read your service manual.
Wear gloves and safety glasses - an accident can happen at any time and are unforeseen.
HVAC can be repaired.

Ensure the kit supply hose is purged of air.
Connect 'gun' to HVAC service valve,
Wearing gloves, loosen hose at 'gun' for less than a second - using the system's gas for purging the air from the hose, tighten fitting.
Good to go.

Start engine, turn on A/C, idle up engine rpm, and about five-seven minutes later, check gauge pressure. Adjust in short spurts - add - stabilize - measure - repeat.
You might even add a thermometer to dash vent for measuring temp.

If you feel you can't do it, have a neighbor HVAC person show you how.

 

Sounds easy enough. I'll give it a try this Friday when I have off work. Thanks for your help and advice brother

 

Hey guys. It was as simple as a recharge. I had a kit lying around with the gage from a car I previously intended to try it on but never got around to it. Plugged it all up and followed the directions you gave me and on the bottle/box/haynes manual and its working great. Thanks for your help and advice. One problem down, three more to go!

 

Cool, literally!
You're welcome