For a while my AC hasn't been as cold as it should, heading down the highway this morning it was 25 C out - the air con on the centre vent was around 18 C (with the vents set to "face") drivers vent side was around 16 C

On the way home in the afternoon it was 31 C out and the air con was struggling. I stopped at a traffic light and put her in S and gum booted the car up to 120Kph - nice to leave the gaggle behind - I then noticed that it was getting chilly - so I put the temp probe in the centre vent and it was 7 C..

I don't have a clue what is happening here - anybody else have something like this happen?

Mac.

 

You are low on freon. The higher RPMs give the system more capacity - greater suction and higher discharge pressure will allow it to cool more. Either driver everywhere at 120 kph or find the leak and recharge the system.

 

haha..

It's not the refrigerant David - it kept the cool even at low rpm all the way home.

It's happened before even around town - I'd switch from auto to manwell and back and again and sometimes it would get real chilly - low refrigerant would not give this kind of "effect".

 

My 1st suggestion is to get a set of AC gauges on the system and see what you have. If you are fully charged then you will have to start looking at the auto-temp system. It could also be in the blend valves where the heat is not being shut down. Start with the pressures.

 

This info was not in your first post and indicates something more complicated than low on charge. As Jagtoes said I would start by putting a set of gauges on the compressor discharge and suction to get a better idea of what is going on.

 

I have been having the same problem. My system was checked and was not low on freon. The problem with mine and others is a spring on the back side of the compressor that Jaguar is aware of that gets weakened for some reason. The part is now on back order and not known when it will get to the US. In the meantime, I just have to use manual gears to keep rev's up above 2000 when in slow traffic.

 

That is interesting. Please post the part number when it gets replaced. It should be shown on the invoice.

 

I had a similar issue on my 2011 XK. My resolution was replacing the AC direct pressure sensing Valve on the compressor

the symptoms were
1. blowing cold then blowing hot air
2. The low side port shows an extremely high pressure reading when running.

https://jlr.oemdtc.com/69/inadequate...10-2016-jaguar

 

Part came in today so car is going into shop today while I am out of town.

 

That sounded somewhat promising - I forgot to mention I have a 2009 XKR.

Looking in the pdf service manwell I see there is a refrigerant pressure sensor:

"The refrigerant pressure sensor provides the ATC (automatic temperature control) module with a pressure input from the high pressure side of the refrigerant system. The refrigerant pressure sensor is located in the refrigerant line between the condenser and the thermostatic expansion valve."

Whether this is affecting the compressor to limit the cooling is not clear.

Thanks for all the input guys.

 

Interesting because my JEPC Jaguar parts diagram for the compressor does not show any replaceable components inside the compressor.

 

Is that from a pre 2010 David?

I did some more digging into the service manwell - a few other items could be affecting the way the AC is working:

EVAPORATOR TEMPERATURE SENSOR and SUNLOAD/LIGHT SENSOR.

 

It is for cars after VIN B32753 so I assume it is for the 5.0L cars.
The picture for cars before that VIN is different and I assume fits 4.2L cars.

 

Here is the link with screen shots of the Direct Pressure Sensing Valve Replacement for the AC compressor

https://www-odi.nhtsa.dot.gov/acms/c...65178-6903.pdf

 

I'm pretty sure that is not applicable to my 2009 embibb.

Issue is not resolved yet (to hot to work out on the beasty) - took it out last evening - around 28C out - air con running at 16-17 C on centre vents.

 

Ok whatever part they ordered did not fit the compressor, so they replaced the compressor which is just fine with me. AC is cooling at all times now as it should be. Without extended warranty, would have been a cool $1700 at the indie, not dealer! I do not mind paying that $50. deductible in that situation.

 

I may send an email to Jag in Victoria see what they say.

 

That does not surprise me as there are no replaceable internal parts for the compressor shown on the parts diagram.

Some one was asking about the earlier compressors. Here is a diagram for the 4.2L cars. Also, no replaceable internal parts shown on parts diagram.