Car has been there for a full inspection and I have been told that the noise is 10000000000% confirmed coming from the air suspension compressor. He is now inspecting for a leak as he suspects a leak in a line somewhere . I was also told that I need various suspension bushings. I'm waiting for a list of what I need.... Will get back to you guys soon....

 

And don't there seem to be an awful lot of them ! FWIW, the main short life bushes are on the rear lower wishbones, and bottom bushes on all four air spring units. These four rather small bushes take the full weight of the car. Fronts are on the lower wishbone, and rears on the air spring unit itself. I have had to have rear lower wishbones and rear air spring bushes, plus a rear track arm, (ball joint shot). Much better prices via internet suppliers. Those little bushes are about £20 here in the UK, although labour charges do add up for suspension work.

 

The compressor will make noise while it is inflating the system, mine always has and dealer says it is normal.

 

I'll vouch for that, too!

Cheers,

 

Ok so here is an update from my service technician. He was shocked at how clean it was under there. Not a leak or drop of anything to be found anywhere!!!!! Some worn bushing in the rear control arms and tie rods but not bad only showing early signs of wear n tear. Tranny was fine engine purring. Now on to the issues. The suspension. A leak was found in one of the lines near the resovoir in the trunk and fixed and the rear no longer drops over night. Problem in rear solved. The front is still under inspection as well as the pump. They are doing over night tests so I should know Tom. I was also told that the pimp is not supposed to make ANY NOISE REGARDLESS OF TEMP! The noise is occurring for two reasons. One is I hit something and damaged the brackets for the pump and need new bushings if they even sell them. And the second reason is because the pump is being over worked causing it to make noise. I was also told I might need both front shocks. When I asked how can both go at the same time he told me that if one shock is bad the pump keeps pumping and my over inflate it causing damage. This I don't buy but my cousin who is the service tech is as honest as can be and he has been a BMW service foreman for 15 yrs. he knows his stuff guys. Other then that suspension crap we are working out I'm happy to report that 77000 miles on the clock and she is immaculate !!!! We shall over come !!! Lolol

 

just found out i need 2 front shocks .... both are leaking...

 

thats also the reason the compressor has been making noise because its being over worked

 

I'm going to have to disagree with your BMW guy. I have been around these cars since they were introduced and have NEVER seen two air springs fail at the same time, except due to body damage. The overwork theory is bogus. Even if a leak exists, the pump [compressor] is controlled in a manner to prevent overheat or damage. It runs for a few seconds then rests. If the pump is EXCESSIVELY NOISY, then it will require replacement. The pump runs to fill an air reservoir, and the reservoir fills the air springs when needed. If there is a leak, the pump will be noticed running even if the car is off, the system will level a car whether it is running or not.

On top of all this, I haven't seen anyone say the car has showed a "Vehicle Too Low" message on the instruments. That usually shows up before anyone even notices anything with the suspension or noise from the pump.

My two cents.......

 

Ive seen 2(actually 3) fail. Maybe not at once but by the time they came in and i hooked up my test gauges to each one. 1 blown, 2 leakers. The issue is that many dont know how to properly diag. And since 1 leaker will pull down the car either in front, rear, or 1 side. You can get that type diag. Yes the compressor runs only enough to fill the reservoir. But if your driving with a leaking air spring the compressor will be coming on more often. Not running longer like steve said. This can eventually weaken the air output to not fill in the required time evne though the compressor may actually still be capable of full system functionallity. Just not fast enough. Kinda like filling a tire with the 300 psi emergency air compressors. Yeah itll go to 300psi. Just takes an hour to get there

 

Quite right, Bill. I shoulda been a little more thorough. One leaker pulls a SET down, 99% of the time. That's where someone usually, erroneously, assumes they must have TWO failures. I'd bet 30-40% of air springs are replaced needlessly for that reason.

Thanks for keepin' me honest!

Cheers,

 

I am impressed by the tremendous wealth of knowledge pouring out over this complicated and frustrating issue, but surprised at the divergent prognoses. Having a busted shock or a sagging spring just ruins the whole Jaguar driving experience I know- I bought my machine with 79k on it, and the front and rear bushings had cracked around the perimeter, and the lube I guess had vanished. There was one Arnott unit on the front, and the Nitto tires had become hard as a rock. The ride was awful. New tires improved the scene dramatically, but the front still hops over moguls. The air system is apparently intact and functioning properly; therefore, it must be the hydraulic aspect of the shock itself which is starting to suck. Is it possible for the air ride feature to work fine, and the shock to fail? Sorry if this post is in the wrong thread....

 

Absolutely!! Especially the Arnott units. The shock portion was probably just painted. One reason I stayed away from them.

 

Not entirely true. The pump never runs when the car (key) is off.

With the car in sleep mode, only lowering is allowed. It will not attempt to raise a leaking shock.

 

not enitrely true, some are new. I know because I just shipped them 4 new ones that the bags were not sealed correctly from the factory and they leaked. jaguar never called for themand were tossed. So thats 4 new shocks(3 fronts and a rear) they rebagged

 

Ok but how do u explain the water and soap test which caused both fronts to bubble at the tops of the shocks?

 

Osmosis????
GREENHOUSE GASES???

 

It is 100 per cent true. I used the word PROBABLY! 4 out of how many. They do claim to check them out on a shock dyno but wear is wear. What is the average life of a shock. I would say they are over the hill at 40 to 50k which is where most of them start to leak. I would say the chances are 90+ per cent you are getting a used shock.

 

Omg now I'm confused... I'm debating just trading it in for m3

 

Air Bag Flatulence!!

 

But still better than LOTTERY odds yes