1954

My 06 C6 air conditioning has been blowing warm for about 6 months. Since the weather has been heating up I had my mobile mechanic attempt to repair. He ran the dye, replaced a couple fittings and re-charged the system. It was blowing cold for 2 days, and now blowing warm again. Compressor is working. I had the dealer replace the radio (warranty item) about 6 months ago. My mechanic thinks they may have punctured a hole when replacing the radio. 2 months ago I had a Pioneer DVD unit installed. The air was definately not working before that unit was installed therefore the installer wasn't at fault. I got to take it to the dealership for proper diagnosis but I'm wondering if anyone has an opinion on whether it's possible that something may have been punctured when replacing the radio. If so, I'm sure the dealership will deny with an aftermarket DVD unit installed. Your thoughts appreciated.

glass slipper

Hard to believe somebody could puncture the evaporator while replacing the radio even if they were trying. It's forward of the radio in the center of the dash but it would take one hell of a long screw to get to it. Did the dye show up anywhere since the system lost its latest charge? Did the mechanic pull a vacuum on the system before he charged it? Does your mechanic have a leak detector (sniffer)?

If you had the system "checked" six months ago, the seal inside the caps for the gage connections may have fallen out and the mechanic may not have noticed. Not many know most schrader valves leak by and the cap is what does the final sealing. Check the caps for the seal up inside and replace any cap missing the o-ring. A vacuum test most likely won't reveal a leak at the caps.

WARNING: Do not remove the cap for the high pressure line while the compressor is engaged/running. Turn off the engine and allow the pressures to equalize before removing the cap. That's straight from the FSM and it's not a BS warning...you could lose an eye because the cap could come off like it was shot out of a gun (and it'll sound like it too). Do it once and I can promise you'll never do it again.

TCW

Since the system was cooling well after a Freon recharge and now it isn't, I'd have to say that you still have a pretty bad refrigerant leak.

There are NO refrigerant lines inside the car so it's imposable that a line was cut during a radio replacement. There are some HVAC vacuum control lines in the car but none in the area of the radio as far as I know.

Tom

1954

Thanks guys, I was hoping it wasn't due to a radio installation. I'll take it to the dealership.

schilitj

could be they over charged the AC unit with freon, let some out and see if that works. Same thing happened to me and the fix was to reduce the freon.

good luck.

LEAVINU

Saw a post about this 3yrs ago or so. Something along the lines of the factory was installing 1.4lbs of freon vs 1.1lbs which was causing a high pressure issue and the system would temporarily turn off.

How did you about releasing some from the system?


My car recently has been cutting the a/c off for a min or two then once I get rolling again it will come on. Very odd and ANNOYING! Thought it was tied to the coolant temps but as of late I dont think so. Now I believe its tied more to humidity and ambient outside temp. Anything over 95deg and its a/c drama for me.

saplumr

I'm not sure where you got this false information but none of it is true. If any needle valve leaks at all you to replace it plain and simple and this can be done with a specific core replacement tool with system fully charged. I've been in the plumbing - HVAC business for 38 years and have never had a cap fly off and we check systems every day running and under high pressure.

saplumr

The dealer has to evacuate the system and weigh in the correct charge.

glass slipper

Do you even have a FSM??? The information I gave is right in the GM Factory Service Manual...how about you call the engineers at GM and tell them about their "false" information. Let me know what they say after they stop laughing at you.

FYI, I just had a cap "fly off" last month and hit my fingers...the next thing you're going to tell me is the pain wasn't real either.

The systems you check have metal caps while the systems on cars have plastic caps. The metal caps you work with have female threads that thread directly on the male threads of the test port. The plastic caps have male threads up inside of the cap that thread into female threads in the test port...those threads are much smaller and made of plastic. When the schrader valve leaks by (and most of them do), there is pressure under the cap. If the compressor is running, the pressure on the high side can get to 260+ PSI...now start unscrewing the cap and see what happens when you get to that last small plastic thread. Don't look too close because that last thread will fail and you'll get an eye full of cap. I don't care how many years you have working on home A/C systems, I'll trust what the service manual says...especially after I've experienced the results of "forgetting" about the warning first hand. Thankfully I didn't pay the price of an eye...for the sake of our fellow forum members, please don't continue to make posts saying my information from the FSM is false unless you plan on assuming the liability of their medical bills and are interested in carrying the guilt of them being blind in one eye for the rest of their life.

Yes, I'm very familiar with the core replacement tools and their different depending on which refrigerant is being used in the system. They're also not the same as schrader valve tools for tire valve cores. And yes, I replace the cores if they're leaking bad. But now to the portion I bolded above in your post...are you really saying all cores can be replaced with the system fully charged??? On home systems you can but not on car systems...two totally different set-ups. While you can isolate the schrader valve on home systems, you have to evacuate/recover the freon in car systems...once again, it says so right in the FSM. If people follow your advice, all their freon will be discharged to the atmosphere and the EPA can fine them. Are you going to pay their fine too???

TCW

FYI. It's against the law to release freon into the air. Don't let a nosy neighbor see you do it!

Tom

rrpederson

hmm, not the same car but in my 03 cobra the heater core took a crap and was blowing hot air all the time. maybe its something similar? i dont know much about the corvettes, but im trying to learn. just throwing the idea out there.

richie

MDPD23

My '05 had the same problem. Turned out the the radiator grill for the A/C was completely clogged with dirt. NOTE: I did have over 100,000 normal miles on the car. No racing or off road running.

saplumr

First of all I'll clearly state if you don't know how to fix something correctly don't attempt it and no I would never advise anyone to potentially purge any refrigerant into the atmosphere intentionally os accidentally. I'll make this as simple as possible. The key is knowledge and proper equipment/tools....you either have them or you don't. Obviously some don't. Also I'll correct a few of your statements. First is we are smart enough to sense any excessive pressure behind a service cap and would never allow any cap to dangerously "fly off". That you admit to such is embarrasing and I can assume inexperienced. Next, most equipment manufacturers have ben using plastic service caps for over 10 years. And finally, homeowners and auto owners do not fall under the same EPA penalties of potential 10 year jail time and $25K fine. We can be fined if we are caught without proper equipment on the truck. Homeowners and auto owners can basically do as they well please. Knowledge is very valuable.

glass slipper

Wow, you must have a very sensitive hand to be able to "sense" excessive pressure THROUGH the cap or you're psychic.

Now we get to the real reason, you're perfect...what a great world your mind must be to live in. Seriously, I make mistakes all the time and fall well short of being perfect. I find no embarrassment in admitting I'm human and hope others learn from my mistakes. Trust me, the flying cap wasn't even close to my worst...

http://www.epa.gov/Ozone/title6/608/...html#noventing

"Effective July 1, 1992, Section 608 of the Act prohibits individuals from intentionally venting ozone-depleting substances used as refrigerants (generally CFCs and HCFCs) into the atmosphere while maintaining, servicing, repairing, or disposing of air-conditioning or refrigeration equipment (appliances)."

Curiously, Section 608 of the Clean Air Act as amended July 1, 1992 doesn't agree with the bolded part of your last paragraph. Also, the fine is up to $37,500. The original fine was $25,000 then it went to $27,500 followed by $32,500 before increasing to the present amount...looks like it's been awhile since you got your certification. Maybe you need to get some more of that valuable knowledge.

PS At least you stopped denying what's in the FSM...maybe you're just a little less than perfect.

saplumr

This pissing match is getting old. What you don't understand is the consumer can always say it was accidental thus no penalty. As far as any fine goes, you have to be caught in the act by EPA rep so the chance is virtually non existent. I've never even seen one. As far a the flying cap being "perfect" has nothing to do with it but being "stupid" has a whole lot to do with it.

LEAVINU

So I went by the dealership this afternoon and explained my warm air issue. Three possible things is what the guy told me:

1) to much freon

2) fan module issue, speed based

3) the compressor


He explained to me that one of the 3 is causing the high pressure saftey valve to trigger hence the warm air. Once you get moving the ambient air flowing through the condenser kicks the a/c back on. I asked about the freon option and he quoted me $120 to remove, weigh and refill the freon (basically a recharge).

5 Liter Eater

You should be able to see whether the fan is running or not so that test is easy.

I would invest in an AC gauge set and measure the low and high side pressures. If the high side is exceeding 300 then the PCM is disengaging the compressor like the tech said. If that is the case then you can let some out (from the low side) until pressure stays under 300 when idling standing still.

If you're not comfortable with doing that then just pay him the $125 to recharge to spec.

LEAVINU

For me its definitely not a fan issue. You can hear that sucker inside the car with the radio on and the cam hitting a lick.

I'm confident my drama lives within the freon level.

glass slipper

There are plenty of EPA reps out there, one lives across the street from me and is always looking when I change the oil asking me if I'm getting every single drop. It's awfully naive of you to think the chance is zero just because you've never seen one. The next thing you'll be telling us is a tree doesn't make any noise when it falls in the forest because you weren't there to hear it. And don't forget about the $10,000 reward for turning in somebody for violating EPA laws against venting freon...think that might motivate one or two people to call the EPA???

Ahh, back to the "flying cap". I usually find the people who can't defend their position always resort to name calling. Am I ignorant??? Yeah, about as ignorant as they come but ignorance is just a lack of knowledge and nobody knows everything in the universe, not even close. Do I make mistakes and do stupid things??? Sure, way more than my share and I don't have a problem admitting that...I can keep people laughing for hours telling all the stupid things I've done but at least I can laugh at myself and don't try to pass myself off as "perfect". Am I stupid? Not hardly because "stupid" means you don't have the capacity to gain knowledge. For example, stupid would be remaining in a pissing match even though all the **** repeatedly gets all over you...yet you keep coming back.

saplumr

Reading and comprehension is fundamental. I didn't say "zero" % chance of getting caught and I didn't call you stupid but I clearly did say what you did was dangerously stupid. As far as your neighbor goes, so what. You repeatedly post the laws we all know exist but does this mean you even have any clue as to what goes on in this industry....absolutely not. The law was put in affect to scare business owners and service techs into compliance and we do comply. The $10K reward, sounds great but again proof and enforcement but with your vast knowledge I'm sure you know of some. I'll stand by my statement of never seen or heard of any enforcement official since we have been required to be certified by the RSES in the early 90's. The federal goverment has important things to deal with. As far as being "perfect" I have been in a successful business for 38 years and and we do strive for perfection. You can read and post all you want but you will never have any idea as to what actually occurs in this industry on a daily basis...no matter how hard you try, wish, think, speculate, bs, talk to your neighbor or guess and even attempting this is quite comical.


footnote: All the above info is just something I pulled off the internet and probably none has any basis or credibility except for the 38 years of being in the industry and 30 years of owning my own business which pales in comparison to the peristence, experience and knowledge of slipper. When I'm wrong I'm man enough to admit it and I admit it. I really have no idea why I even questioned slipper. I now bow down. Some day I hope I can be forgiven.