Pontiac G8 Forum banner
1 - 14 of 14 Posts

·
Registered
Joined
·
9 Posts
Discussion Starter · #1 ·
I have a 2009 G8 V6.
The AC quit working on my car.
But I noticed the AC clutch was still turning.
And the system was fully charged still.
I replaced the low pressure sensor. To no avail.
So I assumed the AC compressor clutch was locked up.
So I took the AC compressor off, and looked at the clutch. It was unlike any clutch I had ever seen before on over vehicles.
I took it apart, and it was completely baffling to me but this would work the way I am used to seeing AC clutches work.
So I just bought a new compressor and a new low pressure switch.
The new compressor belt pulley did not spin by itself, as I am accustomed to on older cars. The clutch would spin as well.
So I went ahead and installed the compressor and the low pressure switch. And recharged the system.
My AC now works wonderfully.
But..... The AC clutch looks like it's spinning all the time. Just like it was before.
Is this compressor belt pulley designed to not spin independently of the clutch??
Would that not make the compressor be engaged at all times, even when you have the AC button turned off?
Confused..

Paul
 

·
OGOC Member
Joined
·
2,649 Posts
Dumb question, is your defroster still on while you're checking it?
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #5 ·
That's what I'm talking about..
The one style is the clutch on my g8, the other is the style that was on my 2002 Pontiac Grand Prix that I had before the g8. The Grand Prix beltway would spin independently of the clutch. Not the case on my g8.
Should the belt pulley be spinning independently of the clutch?
The way it is installed with that ring clip, I don't see how it could spin independently.
 

Attachments

·
OGOC Member
Joined
·
2,649 Posts
Yes I do. I've never heard of this problem on our V6s. I just sounds like to me a relay isn't working properly.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #7 ·
Do me a favor....
When you have a chance, go out and pop your hood.
With the AC off, see if your clutch is spinning.
Unless you have already done so and know for a fact that it is not.
I had my car scanned, and no codes came up.
I'm just at a complete loss.
 

·
Premium Member
Joined
·
4,700 Posts
The compressors used on the G8's are the type that run "full time". Their spinning action is the same weather the system is turned on or off. The compressors have an internal variable pump/vane piston action (so to speak). That variable movement within, is what causes the refrigerant to compress next to nothing (equal to the off position) up to its max output when required. I think there have been a few compressor shafts break inside. The A/C system would stop producing cold air, but to look at that spinning compressor, you wouldn't know that anything was wrong with it.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #11 ·
THANK YOU!
I've been trying racking my brain trying to figure out how the thing works.
That all makes since.
Don't understand why they went to that system.
From what I understand, there's not many cars that have that type of compressor..
But it is what it is.

Thank you again for the info!
 

·
Registered
Joined
·
698 Posts
G8s use an externally controlled compressor, where the internals are always spinning and controlled by the outer solenoid by pulse width for compressing from 0 -100 %, the center area of pulley should be spinning also constantly while eng running, that mid section part uses 6 plastic dowels for pulley to comp shaft mating, if dowels break the center section won't move.It is a very efficient design as the comp is not fully loaded when on as the earlier designs you mention
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #13 ·
Well, all I got to say is....
My old one must have been bad, as when I replaced it with the new one, my AC started working..
VERY HAPPY about that.

Thank you fellow G8 owners for your input!

DRIVE ON!
 

·
Registered
Joined
·
220 Posts
I have a 2009 G8 V6.
The AC quit working on my car.
But I noticed the AC clutch was still turning.
And the system was fully charged still.
I replaced the low pressure sensor. To no avail.
So I assumed the AC compressor clutch was locked up.
So I took the AC compressor off, and looked at the clutch. It was unlike any clutch I had ever seen before on over vehicles.
I took it apart, and it was completely baffling to me but this would work the way I am used to seeing AC clutches work.
So I just bought a new compressor and a new low pressure switch.
The new compressor belt pulley did not spin by itself, as I am accustomed to on older cars. The clutch would spin as well.
So I went ahead and installed the compressor and the low pressure switch. And recharged the system.
My AC now works wonderfully.
But..... The AC clutch looks like it's spinning all the time. Just like it was before.
Is this compressor belt pulley designed to not spin independently of the clutch??
Would that not make the compressor be engaged at all times, even when you have the AC button turned off?
Confused..

Paul
Work your way through this link to ADAIR Technical Service Bulletins. ADAIR made the airconditioning system for Commodore/G8.

Somewhere in there it explains how the Aircon compressor works.

Look at TSBs that mention Holden VE. There is one on "strategies" that goes into AC Compressor not working.

 
1 - 14 of 14 Posts
Top