Dropping Suspension

[Nicholas]

Hi any ideas on this.
After driving suspension has started to drop, front only, after switch off. Start up and it rises.
I was told this is normal in the cold... but have my doubts.
Was also told to give it a long run and it will sort it out. It hasn’t.
Warning light only says ‘vehicle too low’. And red warning light.
There is no fault warning ie: Suspension fault.

Will a diagnostic show the fault and where it is? Even though it’s not showing a fault?

Any help appreciated

[J44EAG]

I had this when my car reached a mileage of 80K. The result of a worn air compressor piston ring. Pulled the compressor out of the N/S front wheel arch, took it to pieces and replaced the old ring with one of Bagpiping Andy`s (Kirby Engineering) long life replacement rings. Cost is around £25 via ebay.

Go to the X350 suspension section and peruse the posts there. One of mine defines doing this job with images of the job in progress.

Once the ring had been changed, the front of the car stayed up instead of deflating overnight.

Mike

[Nicholas]

Hi thanks for reply. Forgot to say car has only done 54000. Also seems to be lower on passenger side. Hoping it’s a small fix. Doubt it a diy job is it?

[davidr]

Refurbishing the suspension air pump is not that hard and can be done with basic hand tools. No special tools or facilities needed. It's requires taking the front bumper off which is easiest on a ramp but can be done on the floor.
Have a go! You'll be so pleased when you have!

[Nicholas]

I would love to. I used to do all the work on my past cars... but age and busted knees have put a stop to all that! Which is sad really

[davidr]

I doubt you'll find a workshop prepared to do the fix Mike suggested. They'll most likely want to sell you a refurbished air pump at £300ish plus fitting because that has less potential come back for them.
In that case, it's best to make sure what the problem is! It would be normal for the car to throw a suspension fault code if the pump piston rings are worn as there is a set time that the car expects the pump to run before the air suspension system comes up to full pressure. If it takes longer the usual fault is "Reservoir implausibility error" because it assumes there must be a leak. It doesn't sound like you have an error? What you don't want is to pay for expensive workshop time to fix the wrong problem.

[J44EAG]

I agree with my friend, David.

A pump overhaul is great for a DIY guy but a garage will as David says, want a guaranteed first time fix and not have to go in again if the overhaul is unsuccessful. A trawl on eBay will often source a brand new OE pump for around £300. Its a 3/4hr job if you gp in through the wheel arch liner. The bumper off method also works but you then have to tackle the multitude of corroded screws and bolts attaching it to the front edge of the engine undertray. I prefer the wheel arch liner attack!

A valve block issue adjacent to the air tank in the boot can often give problems. Eurojag who advertise in our magazine can often turn up a decent second hand unit. Generally breakers prices are about one third of the cost of new and the breaker will supply with a short warranty. The problem now is that these cars are beginning to suffer age related issues that eventually come to all cars. Good used parts are beginning to become more difficult to source although there still appears to be plenty of genuine new OE and some good aftermarket parts around at fair prices. Best advice for electronic sensors, thermostats and other consumable items is to buy genuine new Jaguar sourced and supplied parts.

Remember these cars will attempt to self level themselves when ever possible after parking. Its part of the sleeping pattern. In good condition now, my car on semi-level ground outside the house, self adjusts as I get out and lock up. I love to hear escaping air from the compressor and watch one of the front struts deflate to level the car. Better still is coming back to the car exactly twelve hours later to watch the car start moving up and down as it once again self adjusts. By-standers stand in amazement as it does its little dance!

None of that occurred when I had the worn piston ring. I caught that before it wore out completely which would then have wrecked the cylinder bore of the pump.

Like many Jag owners, as they age in direct proportion and effect to their pride and joy, I`m now also affected by advancing age, a collapsed back and sciatica. Should my car have a chassis level problem tomorrow when it goes for the MOT, I`ll have to make a decision as to whether I could now tolerate and endure the pain of perhaps having to change out a suspect wheel bearing cartridge. Three years ago, I pulled the car to pieces. Three years on, I`m not so inclined especially at this time of year. It comes to us all.

Like Slough, I was alright but I isn`t now! I fear another trip to Surrey Jag Centre on the horizon.

Mike

[Nicholas]

The jag is an x358 it’s 2007 with 54000 miles. I don’t think this is a self levelling thing. It’s right down. Yes it rises when started after about two minutes. Can this be the reservoir? Pump? Just don’t have error code. Happy for a garage to replace whatever but not pay them to chase rainbows

[J44EAG]

That does rather sound like a worn pump.

Although low mileage, it is the amount of use that pump gets that wears it out. A short journey car that has 54k miles might conceivably have more pump wear than one that has done 150k miles of motorway mileage. A clapped out piston ring obviously influences the speed at which the car pumps up its suspension. Mine, with a new ring fitted, now rises immediately and switches off in a few seconds.

Have a look on eBay for OE grade compressor pump replacements if you don`t want to go the Bagpiping Andy ring replacement route. You will find quite a variation in prices on eBay. Look carefully at what is being offered and then find the best deals. Second hand units are a huge gamble so I`d suggest you stay clear of them. Also chat to Neville "The Devil" Anderson at Jaguar Spares North East. Tell him you are a JEC member. I hope you can translate broad Jordie! Nev is a good fellow operating a family run Jaguar spares supply business. He is a good as they come and you will find him very helpful.

A compressor change will take little more than an hour. Once accessed either via bumper cover removal or by removing the NS wheel arch liner, removal of three bolts, a mounting plate and disconnection of the air lines, has the pump off the car.Expect to find the tinny two part sheet metal mounting plate in a very corroded condition. Clear up and repaint if in sound condition or if virtually disintegrated, source and new plate and perhaps also the springs between the plate and the compressor. That plate can get in a right old mess!

Hope that helps.

Mike

[Nicholas]

Thank you so much for this information. Much appreciated

[Nicholas]

Ok, I’ve had a new pump/compressor fitted. Jag is still dropping at the front..
Mechanic has been all over the car and can’t detect any leaks...
Any ideas what else can cause this? Cold weather? Bushes?
Or is it just something it’s going to do. Was fine until one cold morning I came out and it had dropped.
I have taken her for relatively short trips and front dropped minutes after parking.
Please help
Any help is appreciated
Thanks
Nick

[J44EAG]

Is this a moderate drop or one that has the underside of the front bumper touching the ground? Expect to see some drop as you get out if the car is parked slightly uphill.

Mike