Well it happened. My first issue with the new (to me) car. The dreaded
air suspension problem.

I have to say that this forum has been a lot of help. There are so many threads on air suspension experiences, I thought twice about adding another.
It started about 2 weeks ago. The orange light + CATS System fault message.

I thought it was an isolated error as it came up and then cleared less than a minute later. It did not re-appear for 3 days. However in the last week it has gotten to the point that city street driving it is on 30% of the time, and highway 75% of the time the car is in motion.

I initially suspected (and still do) the compressor. The car now has 71k miles on it, and I have learned in these forums that if that is the original compressor, its probably over due to fail. The reason I suspected the compressor, is that the issue clears and the car is able to level itself. If I'm city driving and come to a stop light, and the light is long enough, the CATS system will recover and the error goes out. I often feel the car come up in the rear when this happens. Its almost like the compressor is not supplying enough pressure while the car is in motion and making adjustments, but is able to catch up if the car is stopped long enough.

I found many useful threads on checking the grounds (earth points). I was able to check and reseat all of the electrical connections to each air shock, as well as give the soapy water test to all the connections to all four after pulling out the trunk liner. I also check ed the connections at the reserve tank.

Doing this, I discovered that the right front shock is a replacement. It differs in looks from the other 3, so the previous owner had already dealt with air issues since the carfax was clean. I'm assuming no accident.

While I didn't find a leak at these connections, I think there may still be a leak somewhere in addition to a weak compressor. If I do not drive the car for more than 12 hours, it starts to sink significantly at all four corners (worse in the rear, however). As soon as I start the engine, it raises back up.

Anyway... tomorrow it goes to my mechanic who is going to look for the problem and we are going to discuss conversion kits.

I just wanted to post a thank you to everyone else who have given me clues on things to look for via their own experiences, and I'll update what eventually is the solution, and if I choose to just chuck the CATS system entirely.

 

David,
I just suffered through issues with the air suspension when I bought my car in Florida and drove it to cold WI. I feel your pain.
I read as much as I could on the system, and to be honest, it isn't as complex as I thought.
Now, I never got a CAT system warning light. Mine was an air suspension failure light. However, mine is a 2004, so maybe that changed.
The fact that it drops while parked sure makes me think it is a leaky shock. If one shock was replaced, but not the others speaks to that possibility.
In the end, the compressor rebuild is not difficult or expensive.
The shocks are super easy to replace...did both fronts on mine in 1 1/2 hours without help.
Seems those in very cold climates (like me) are prone to conversions to rid the air suspension issues, but Phoenix shouldn't be a problem. The shocks are pretty reasonable through Arnotts.
Don't bail in the CAT setup so easy...read everything here and see if you can't figure it out. There are so many very smart people on this site (and very generous) that you can solve the issue. Good luck!

 

Thanks. I did read your adventure from florida! It was quite a story and a beautiful car BTW!

It is at the mechanic now. I'm not using the dealer. I have an independent shop where the manager and one of the techs have extensive Jag experience.
I'm just waiting for a call with their conclusions.

I would love to do everything myself, but Condo living limits my space.

I also forgot to mention that I tried pulling some codes myself, but the Innova 3030e that I have didn't pull any codes. It connected OK, but gave a green light with no codes. I will probably need another model. I had that one already, so I gave it a try.

I won't give up on the CATS system right away, but I only paid 15.9K for the car, so really for me its an issue of value of the car vs cost of repair vs conversion cost. I just need to weigh it all once the mechanic has a verdict.

 

Keep us posted...

 

Well its the left front. Shock is leaking. I mentioned the right front was already replaced. I'm going to have it replaced. I hope that is the end of CATS issues for sometime.

But a new development in the Catalytic converter area. It had been idling a little rough in the mornings when the engine is cold. When he pulled the codes it returned a P0430 (Catalyst System Efficiency Below Threshold (Bank 2)).

The car has 71,420 miles. It was manufactured in 11/2005. I don't know what the "in service date" is, but it shouldn't matter. The catalytic converter is warranted for 8 years 80,000 miles. I'm still, barely, inside that window even working from manufacturing date. The service engine light is not on .... yet.

My mechanic called the Jag dealer and they told him that Jags are only 70,000 miles, so I just missed it, sorry, too bad, Jag doesn't make exceptions.

If you go to Jaguar's own website they say 8/80 on 2006 models. The EPA website says 8/80 on any vehicle manufactured after 1995. I believe its Federal Law.

I now have to press this issue once the suspension is done. Maybe he talked to someone without a clue, or maybe someone who just didn't want to deal with an independent wrench. I don't know.

I'll let you guys know what happens when I go directly to the dealership myself.

 

Well, my understanding is that CATS varies the shock absorber setting from hard to soft depending on the stance of the car, and what it is doing.

So - on braking it stiffens up the front shocks, on acceleration it stifens up the rears, cornering it stiffens up the shocks on the roll side etc.

The air springs themselves are not varied.