I know there are many posts on this subject but they don't address my issues.

I am getting a "CAR TOO LOW" message every now and then. The local Jaguar dealer could find no fault but I can hear air escaping from the front of the car.

I've seen comments about changing the seals on the compressor. Can someone please tell me where I can buy the seals (part number), where the compressor is and how difficult it is to change them?

I was thinking of getting rid of the air suspension by installing coils over shocks but I'd like to retain the original ride.

Thanks for any help.

Stephen

 

If you are getting regular hissing, then you have a leak which you'll want to address soon before it takes out the pump seals too. Follow your ear to the hiss. The pump is under the left front fender behind the bumper. You have to remove the big black wheel well guard to get to it. There is a fellow on this site who sells replacement pump seals which will extend the life of the pump, whereas the dealer will simply swap the whole pump. The pump sends the air back to a tank and distribution block in the trunk, from where it then goes to each of the 4 shocks.

 

When do you hear this hissing ? All the time ? Reason I ask, is because at the end of a reasonable run the ASM will exhaust some air back out of the compressor air inlet to blow the water out of the water trap. This sounds like a "whoosh" noise and lasts several seconds before ceasing.


"Vehicle Too Low" is the more serious of the two suspension messages, so needs investigation. I am very surprised a Jaguar main agent found nothing, as when you get a fault message, a fault code is stored at the same time. However, if you did several trips after the message disappeared, the code may have been deleted. You will see in the Owner Handbook that if you get this message, you should take the car to a dealer asap.

 

Bagpipingandy.com is one site to buy a rebuild kit for the compressor, but it sounds like you have a more serious issue to resolve first.

According to my manual, you are not supposed to drive the car-- that error message essentially means there is reduced or no air in your air shocks. I had that error last year; the front of my 04 XJ8 could not be turned more than 10 degrees or so before the wheels would rub the fender wall and the front end had no suspension at all. The car was resting on the nubs--it was about 6 inches lower----it was dangerous to drive it.

When you're ready, it's an inexpensive and simple job to remove the compressor and rebuild it. As I recall, there are three bolts that mount it to the frame left front behind the bumper plus an air line and electrical connection. Rebiuilding the compressor is accomplished by removing a few bolts and replacing a rubber seal. The whole job should take an hour or less, using a basic ratchet wrench set.

 

It's not your compressor...yet. The hissing is no doubt one of the front air shocks. Best to replace as a pair anyway, so it doesn't really matter which one. If you replace them timely, you will save having to repair the pump too.

 

I agree with cjd. In my case I had a leaky front shock in cold weather (after only 147,000 miles), so I replaced both front shocks with Arnotts and the problem was resolved.

 

Hi Stephen,

As rhankey suggests, try following your ear to the source of the air leak which may get you in the general vicinity of the problem. You can spritz soapy water on the fittings for the air hoses at the tops of the air spring/shock absorber units and also around, but not on, the electrical connector for the CATS solenoid in the center of the top of the unit. Bubbles will indicate a leak. If you can't tell for certain where the hiss is coming from, test the air hose fitting on the compressor and the fittings on the valve block and reservoir in the trunk under the spare wheel/tire.

If the hiss is constant, other possible sources are a rupture in an air spring bladder (hiss comes from inside the wheel well rather than from the top of the air spring), or the exhaust valve on the compressor is corroded internally and has seized partially open (hiss comes from the front left bumper area).

If the leak is minor, or only occurs in cold weather, you may be able to live with it by replacing the piston ring in the compressor to restore its original efficiency. See the link in my signature for a phototutorial showing how the piston ring is replaced.

Cheers,

Don