AC Expation valve
Thread Starter
8th Gear
Joined: Apr 2009
Posts: 8
Likes: 0
AC Expation valve
Hey, new here with few questions.
Having a problem with the AC expansion valve, 07 C6 ZO6.
I can see the valve, it's located behind the intake manifold and i think i will have to remove the mani to get to that nut that hold the pipes to the valve.
Is it possible to change the valve by only removing the intake manifold or the dash has come out too?
has anybody did such a job before?
Thanks in advance.
Having a problem with the AC expansion valve, 07 C6 ZO6.
I can see the valve, it's located behind the intake manifold and i think i will have to remove the mani to get to that nut that hold the pipes to the valve.
Is it possible to change the valve by only removing the intake manifold or the dash has come out too?
has anybody did such a job before?Thanks in advance.
Race Director
Joined: Dec 2007
Posts: 19,030
Likes: 6
From: Maumelle Arkansas
St. Jude Donor '13-'14-'15-'16-'17
Take it to a dealer
Unless you are an experienced A/C mechanic take it to the dealer. I'm really curious how you diagnoised the problem as the expansion valve.
LJ
LJ
Le Mans Master
Joined: Aug 2002
Posts: 8,472
Likes: 38
From: Houston TX
St. Jude Donor '11
I don't think the C6 AC system has an expansion valve. They use orifice tubes instead. I know for sure the C5's do anyway. The orifice tube is inside the lines running along the passenger side of the engine bay.
Thread Starter
8th Gear
Joined: Apr 2009
Posts: 8
Likes: 0
I'm a certified AC tech, and i do have all the equipment to do any kind of AC job
.The AC used to be working ok, all of sudden the compressor stoped working/engaging so i thought that the system has a leak somewhere thats why the compressor is not engaging. there's not enough pressure to trigger the compressor. I looked for signes of leak but there was none.
Next i hooked up the AC gas recovery machine and it recovered 700g of refrigerant gas which i think is the right amount, Vacuumed the system from all the reaming gas and checked for leaks again and everything look tight, so i decided to refill the system with more than 700g, i added 200g more. during system refill the system didnt wana accept the gas, the pressure got equalized.
So i reclaimed the gas again and this time i decide to put only 700g that was in the system before, but no luck only 400g went in and the system got equalized again
.To make long story short, the expansion valve is stuck close and it preventing the rest of the gas to go into the evaporator. thats why the system get equalized every time i try to fill the gas, and the AC was not working because the system pressure was too high, no too low as i thought in the beginning.
This is how i got it diagnosed
. hope that answer your question.
Last edited by 3000hp; Apr 16, 2009 at 04:55 PM.
Race Director
Joined: Dec 2007
Posts: 19,030
Likes: 6
From: Maumelle Arkansas
St. Jude Donor '13-'14-'15-'16-'17
If the exp valve is like everything else on the vette you have to take something off to get to what you need to work on. Good luck.
LJ
Le Mans Master
Joined: Aug 1999
Posts: 5,411
Likes: 2
From: N Carolina 08 Z51 Coupe
Did you get any kind of a code? Just wondering if the system logged a code.. I would assume so as the pressure sensor would have set a flag..
Thread Starter
8th Gear
Joined: Apr 2009
Posts: 8
Likes: 0
I'm satisfied. From your initial post I was concerned that you maybe didn't have that much refrigeration experience and were just guessing or some "expert" told you it was the valve.
If the exp valve is like everything else on the vette you have to take something off to get to what you need to work on. Good luck.
LJ
If the exp valve is like everything else on the vette you have to take something off to get to what you need to work on. Good luck.
LJ
Thread Starter
8th Gear
Joined: Apr 2009
Posts: 8
Likes: 0
, that would had made my life much easier. most of the equipment i have are for German cars that i usually work on.
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Racer
Joined: Jan 2009
Posts: 323
Likes: 1
From: Lake Worth Florida
I'm a certified AC tech, and i do have all the equipment to do any kind of AC job .
The AC used to be working ok, all of sudden the compressor stoped working/engaging so i thought that the system has a leak somewhere thats why the compressor is not engaging. there's not enough pressure to trigger the compressor. I looked for signes of leak but there was none.
Next i hooked up the AC gas recovery machine and it recovered 700g of refrigerant gas which i think is the right amount, Vacuumed the system from all the reaming gas and checked for leaks again and everything look tight, so i decided to refill the system with more than 700g, i added 200g more. during system refill the system didnt wana accept the gas, the pressure got equalized.
So i reclaimed the gas again and this time i decide to put only 700g that was in the system before, but no luck only 400g went in and the system got equalized again.
To make long story short, the expansion valve is stuck close and it preventing the rest of the gas to go into the evaporator. thats why the system get equalized every time i try to fill the gas, and the AC was not working because the system pressure was too high, no too low as i thought in the beginning.
This is how i got it diagnosed. hope that answer your question.
.The AC used to be working ok, all of sudden the compressor stoped working/engaging so i thought that the system has a leak somewhere thats why the compressor is not engaging. there's not enough pressure to trigger the compressor. I looked for signes of leak but there was none.
Next i hooked up the AC gas recovery machine and it recovered 700g of refrigerant gas which i think is the right amount, Vacuumed the system from all the reaming gas and checked for leaks again and everything look tight, so i decided to refill the system with more than 700g, i added 200g more. during system refill the system didnt wana accept the gas, the pressure got equalized.
So i reclaimed the gas again and this time i decide to put only 700g that was in the system before, but no luck only 400g went in and the system got equalized again
.To make long story short, the expansion valve is stuck close and it preventing the rest of the gas to go into the evaporator. thats why the system get equalized every time i try to fill the gas, and the AC was not working because the system pressure was too high, no too low as i thought in the beginning.
This is how i got it diagnosed
. hope that answer your question.There is also a refrigerant pressure sensor that could be bad. If the sensor is defective, it would not allow the compressor to engage. But that does not answer why you could not recharge the system. You may want to get one of them as well, just in case the TXV isn't the problem.
You should evacuate down to around 500 mic's and then let it hold for 30 minutes or so to check for a leak.
According to the tech manual, you need to remove the intake manifold to replace the TXV.
When you recharge, make sure you use a Polyalkylene Glycol (PAG) synthetic refrigerant oil and NOT a Polyolester (POE) refrigerant oil.
Last edited by Capt Steve; Apr 16, 2009 at 06:07 PM.
Thread Starter
8th Gear
Joined: Apr 2009
Posts: 8
Likes: 0
I evacuated the system down to 350 mic for a 45 min, on the second try i could hear the valve clicking/opining and i could see the gauge bouncing for a second. but the system held vacuum ok.
Thanks for the tip about the oil
, will start by removing the mani first thing, and will see how things go from there.
Thanks for the tip about the oil
, will start by removing the mani first thing, and will see how things go from there.
