THIS CAT DOES NOT WANT TO COME OUT AND PLAY IN COLD TEMPS.... I notice that once the weather drops under 40f I get all sorts of suspension warnings and the front drops low... But above those temps NOT A WARNING LIGHT OR DROP IN SIGHT !!!!!!!!!!!!!! its 25f outside in NY and I went to start her up to make a midnight food run and low and behold the suspension is on the floor and the red warning light comes on .... after about 10 minutes and 4 blocks later the car warms up the suspension goes up and the light goes away to go f#$k its mother..... Im so frustrated that no one can even find the damn problem. Its amazing the lack of enthusiasm and knowledge on these cars... Now I'm forced to go to New Jersey to drop the car off .... What a joke... but its definitely the cold weather... the noise goes away when its warm as well which has me 99% convinced the problem is the air suspension motor.. though it all I refuse to let the ineptitude of others ruin the experience of owning this car.. She is quickly becoming the best and most favorite automobile I've owned in my 37 yrs on this planet #frustrated a little .....

 

I reckon you need a replacement air compressor from the sound of it.

I have yet to work out how the water trap in the compressor is emptied, but suspect it is done by the system blowing some air through the dessicant after a journey, because I hear air exhausting at the front of the car when I stop, but the suspension stays the same height. I surmise that if this blowing out fails to work properly, the dessicant trap will eventually get saturated and then let water into the system, which can then freeze in awkward places.

 

I too, as an engineer, wondered how the dessicant is renewed as I could pour the water out of the one I dissassembled.

 

It's called adiabatic expansion.

The air is depressurised rapidly and periodically which causes water to be removed from the dessicant.

In adiabatic process heat is neither added nor removed from the system. So the work done by the system (expansion) in adiabatic process will result in decrease of internal energy of that system (From I st law). As internal energy is directly proportional to the change in temperature there will be temperature drop in an adiabatic process.


The gas cools below the dew point and free water is formed which is "blown" out.

Bob

 

Jaguar's description is as follows:

 

Yes, that is the exact text from the X350 Technical Notes of 2003 that I have.

It would seem to explain why I get this burst of air after turning off the engine and parking up. However, I would expect it to do it continually during a journey, but obviously we can't hear it whilst driving if it it being done.

 

Doesn't appear to work too well.

 

i just don't understand how above 40 degrees there are no warning lights no noises no suspension on the floor..... There has to be some kind of connection here.......

 

If it is throwing the plausibility error you can bet that it is a leak made worse by the cold and a weak compressor.

 

I am having the same problem, causing the car to ride harsh and clunking suspension. But as soon as the weather warms up the problem goes away. Ha e an appointment at the dealer on Monday, hope they can find a problem.

 

Most likely the expansion and contraction of the air-shock components and seals.


Happy New Years

 

Threads like these make me glad I got rid of my X350.

I'm hoping to get in a (more affordable) X308, though!

 

Not to mention X308s are nicer cars too

 

I had the same problem and replaced the compressor as well as the front air struts with the Arnott units. I can not believe how good my suspension now behaves. It actually feels more compliant and with better control than I can ever remember. I am enjoying my 2005 XJR all over again!

 

Did the new compressor actually help or was it simply the fact that the weather got warmer? I'm considering getting a new compressor but don't want to waste/spend the money if bitter cold weather is still going to cause air suspension- ride to low problems.
Thanks

 

Perhaps you should move to South Florida. Oh, I forgot. That didn't help me.

Sunny South Florida

 

jasedita 74,

Try pulling the air lines, removing the collets, then pull & replace the 'O' rings that the collets lock into place. The high tech soapy water detection of the leaks would suggest that when the existing 'O' seals are cold, they are not gripping & sealing properly. It's a long shot, but perhaps as the engine bay temperature warms up the air, they are becoming pliable enough to provide a managable seal. Age certainly does harden them up. Although not a factory recommedation, I have also used a very light smear of silicon swimming pool pump filter cap sealant when reassembling just to ensure a good seal. The other thing to do is to look closely at the ends of the air lines themselves, for any longitudinal scratches, or annular compression around them where they 'bed' into the 'O' rings. If there is, trim a short amount off the ends, and very gently rotate a pencil sharpener around the fresh cuts to bevel them before reinserting them into the air suspension bag.

Cheers,

Languid

 

Languid,

That was excellent information!
(Seem like the same procedures as repairing Air Brake Systems.)

Added: My left front had an air leak at the fittings, I removed them and found 2 torn O-rings. They were replaced with some extras that I had in my shop. Working fine since.

 

The use of plumbers PTFE thread sealing tape could cure small leaks at threaded joints. Worth a try ?