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2006Rangie



Member Since: 26 Jan 2017
Location: Toronto and Melbourne Florida
Posts: 19

Canada 2006 Range Rover HSE 4.4 V8 Giverny Green
AC Compressor - fixed displacement 0r variable displacement?

Hello,

I have a 2006 L322 4.4L Jag engine.

Recently it started to provide less cool air through the AC system. Numbers were: about 20 degrees C from air vent, 60 psi suction side refrigerant, 150 psi discharge side refrigerant. I mis-diagnosed the problem as a faulty thermostatic expansion valve and went to the trouble of replacing the valve. It does give slightly better cooling at the air vents of about 18 degrees C but the pressures did not change. There was no debris or signs of compressor damage at the valve, which was perfectly clean at the orifices.

I think it is a compressor failure. I am now wondering what compressor to install. My Rave service procedures manual dates back to 2002 and it makes reference to a the compressor being a fixed displacement compressor. However, the 2006 had some significant updates with the Jag engine and I do not know if the more modern variable displacement compressor was originally installed.

The currently installed compressor is a Sanden PXV16 with an LR Part No. JPB500210. I am not sure if this is a fixed displacement or variable displacement compressor. Also, I am not sure if this was the originally installed compressor when the car was factory new. Sanden does make a variable displacement version of the PXV16. In any case, I am wondering if there might be a fuel efficiency or other operational benefit to installing a variable displacement compressor.

I would appreciate any opinions for and against.

Cheers,

Post #488725 12th Sep 2018 4:35am
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John w



Member Since: 14 Jan 2018
Location: Cranleigh, Surrey
Posts: 312

United Kingdom 2011 Range Rover Autobiography Black TDV8 Barolo Black

No idea what year they were changed from, but If you can see it, you can determine if it is fixed displacement or not.
Unfortunately the PXV16 reference doesn't give the answer.

Does the pulley have an electronic clutch ?
If it does, it is fixed displacement.

If it doesn't and the wiring goes to a round PCV (Pressure Control Valve) on the back of the compressor, then it is variable displacement.

There are some pictures of my compressor from my 2010 4.4tdv8, which might help to give you a clue what and where the PCV is. Too many toys, not enough time

2011 4.4 TDV8 AB Black

Post #488752 12th Sep 2018 12:17pm
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2006Rangie



Member Since: 26 Jan 2017
Location: Toronto and Melbourne Florida
Posts: 19

Canada 2006 Range Rover HSE 4.4 V8 Giverny Green

Thanks John.

You are correct that the PXV16 nomenclature does not define the compressor. To complicate things further, variable displacement compressors come in 2 forms:
- an externally controlled form with a solenoid valve commanded by the car's computer to adjust the swash plate
- an internally controlled form with a pressure valve responding to suction pressure to adjust the swash plate.

For sure I do not have the externally controlled form so that narrows my search somewhat. Only question remaining is should I pursue the internally controlled form?

The lazy solution is to just replace the one that is currently installed and I might just do that. But this is an opportunity to perhaps install a better solution.

Attached is pic of nameplate on existing installed compressor.

Cheers,

Post #488760 12th Sep 2018 2:06pm
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2006Rangie



Member Since: 26 Jan 2017
Location: Toronto and Melbourne Florida
Posts: 19

Canada 2006 Range Rover HSE 4.4 V8 Giverny Green

Oops, here is pic.

Post #488865 14th Sep 2018 6:04am
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MikeO



Member Since: 02 Jan 2018
Location: The Cotswolds
Posts: 157

Scotland 2009 Range Rover Vogue TDV8 Buckingham Blue

This one?

Click image to enlarge
 2009 FF Vogue TDV8 Buckingham Blue
<gone>BMW 520D SE (not my favourite car)</gone>
<gone>2009 D3 HSE Galway Green</gone>

Post #488890 14th Sep 2018 2:43pm
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2006Rangie



Member Since: 26 Jan 2017
Location: Toronto and Melbourne Florida
Posts: 19

Canada 2006 Range Rover HSE 4.4 V8 Giverny Green

Yes, that is the one currently installed. Not sure why the picture is not showing up in the thread.

Any comments on fixed vs variable displacement?

Post #488894 14th Sep 2018 3:07pm
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MikeO



Member Since: 02 Jan 2018
Location: The Cotswolds
Posts: 157

Scotland 2009 Range Rover Vogue TDV8 Buckingham Blue

No idea sorry. I was just fixing the picture for you Thumbs Up 2009 FF Vogue TDV8 Buckingham Blue
<gone>BMW 520D SE (not my favourite car)</gone>
<gone>2009 D3 HSE Galway Green</gone>

Post #488903 14th Sep 2018 4:38pm
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2006Rangie



Member Since: 26 Jan 2017
Location: Toronto and Melbourne Florida
Posts: 19

Canada 2006 Range Rover HSE 4.4 V8 Giverny Green

Ok. Thanks.

Post #488904 14th Sep 2018 4:42pm
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2006Rangie



Member Since: 26 Jan 2017
Location: Toronto and Melbourne Florida
Posts: 19

Canada 2006 Range Rover HSE 4.4 V8 Giverny Green

The compressor installation is now done. Installation is successful and I have nice cold air coming out at 6 degrees C.

Overall, I am satisfied with the initial performance of the new compressor over the first 3 days of operation. The new compressor seems to be well constructed. There were 2 concerns:

One related to a lack of documentation with the unit purchased through Amazon from BuyAutoParts. There was no nameplate, no indication of whether it was shipped with oil, etc. Before ordering I had an initial question that the sales people at the BuyAutoParts were unable to answer namely; is this a fixed displacement or variable displacement compressor. I took a chance in ordering it based on Amazon’s customer satisfaction guarantee that it was the correct fit for my vehicle (2006 Range Rover HSE). Upon delivery, I was able to confirm that it seems to have the valve for internal control of a variable displacement compressor and that it was therefore the correct type.



Click image to enlarge


The second concern was in fitment of the electrical connector, which required that I make a small modification in the installation. Refer to the 2 pictures: On the old compressor, the electrical connector was anchored by a specially shaped metal plate screwed on to the top; it had 2 drilled holes for the plastic anchors attached to the electrical connector. On the new compressor, the electrical connector was shipped loose but it had the plastic anchors attached to it. However, the metal plate from the old compressor would not fit on the the new compressor. I had to work around this problem by using a zip tie to hold the electrical connector close to the top of the new compressor.

Apart from these 2 small issues, I am satisfied that the new compressor is the correct design type. It is working satisfactorily and I am hoping that it will last for a long time.

Post #490694 2nd Oct 2018 3:58pm
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2006Rangie



Member Since: 26 Jan 2017
Location: Toronto and Melbourne Florida
Posts: 19

Canada 2006 Range Rover HSE 4.4 V8 Giverny Green

Here is a close-up of the metal plate for the electrical connection on the old compressor. Picture rotated.

Post #490697 2nd Oct 2018 4:13pm
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