I have rebuilt/replaced the entire suspension on the front end of my 04 Jag XJ6.
After a few minutes of starting the engine and setting the air-shocks all was looking good until I finally took it off the jacks and lowered the car to full weight.


Minutes later I heard a long scush of air.
The drivers side shock is now on the floor, as in the wheel is inside the arch and unable to even turn.
I searched on here for cures but got stuck.
I have a few things left to do and would like any advice to help me with this.


I suspect two main problems.
The Air compressor pump gave out on the front drivers side pipe.


I removed the air hose from the top of the shock and turned the engine on.
I felt no air coming out the pipe.
I still have to remove the passenger side pipe and see if air can be felt coming out of this one.


I am not sure if the pipes are always under air-pressure or are they only pushing air at certain times as worked out by the Air compressor-ECU.


As another option, I can remove the new air-shock and put on the old one that was not leaking and worked perfectly and try this but its a lot of work to do for me.


Is there any way with-out a computer for me to check the pump/valves etc, to see if the actual Air-compressor is faulty?


Worst case scenario is the new shock is faulty and the air I heard escape was from a damaged new bladder in the new shock.


All three other wheels and shock height are perfect.
The faulty shock does not even pump up when engine is on.


So I am asking, even if not very good at explaining myself if anything I can check before I run out and buy a new air compressor pump as they are not cheap?

 

Start by raising the vehicle until the tire is completely off the ground. Then lower the vehicle just until the tire touches the floor. Start the vehicle. Lower the vehicle to a height of 380mm from the center of the wheel to the lower lip of the fender opening. Continue to run the vehicle and wait for at least 2 minutes. Then lower the vehicle to a height of 340mm. Do not turn off the engine. The system should then start the compressor and raise the vehicle to it's proper height. If it does not, you will need to start diagnosis with Jaguar documentation of the air suspension, or if you purchased a failed replacement, you will hear it.

 

It's strange that only one corner dropped, it should dropped all the corners after jacking. Play with key turning on and off the engine. Keep patience and car will self-level itself after some time.

 

Thanks for the help on this from above posts.

I had started to finish off the rebuild and last job was to lower the car gradually until I got the shocks rising on their own.

It had gone good and I got it off the jacks and back on allfour wheels with everything perfect.

I was about to get in the driver’s door and suddenly I heard a whoosh of air letting go and I thought okay, maybe the pump compressor settling down after the new shocks been fitted.

I never noticed with-in a few mins after this the driver’s side went down like a burst football.

Only when I reversed and turned the wheel did I notice the tyre rubbing on the inner wing.

I knew then the air I heard escaping was not normal and this is the stage I am still at.

I swapped over both front shocks today to put my mind at rest that the new shock was perfect and the problem was elsewhere. This was conformed when the shock from the driver’s side went on the passenger side and worked perfectly and the driver’s side will not even rise at all.

I found what I think is a good price for a new air-compressor pump at £279 direct from Germany and exact one Jaguar fit, so obviously from same company Jaguar use to get their supply of said pump.

Jaguar dealer wanted £717.19 for same said pump.

Part number for my car pump – C2C27702.

I also found a valve block with colour-coded pipes for each shock and now I’m thinking that the valve for the front drivers side could have failed, this would explain why I have no air to the front drivers side pipe since I heard the swoosh of escaping air.

I will keep updating as I go through the process of curing what happened until I get it fixed.

I do not suspect the ECU at this point and am still leaning towards it been a mechanical failure and not electrical or computer problem.

I will remove the air-pump tomorrow and see if any way I can work-out if it works partly or properly.

All other three wheels hold perfect height when engine running. I have all pressure off the shocks again as I have jacked her back up off her wheels.

 

A common problem with the compressor is that the piston ring wears out. There is a guy called Bagpiping Andy http://bagpipingandy.com/ who makes and sells refurbishing kits which seem to be very well rated by people who have used them.

 

Should not be a compressor issue as the three other shocks can be raised and hold pressure.
More probably, either it's the driver's side front shock that's gone or it's an issue in the valve block.

 

Ah, but he said he'd swapped the suspension units and the fault stayed on the driver's side so that rules out the suspension unit.

As it's a 2004 model I'm just wondering if it has four height transducers (early 350s did) and the one on the F/RHS has gone u/s.

 

I am beginning to lean towards the valve block. Darkness has me this end but tomorrow I'll trace back until I see why no air comes out the drivers side pipe.
A serious air leak has occurred in the system, which I now know is not normal. When I get to the bottom of the air leak it will then let me find why the drivers side front is knackered I'm hoping.


Thanks for the advice on the piston kit but since the whole unit is 12 years old I'm not going to repair it


My car is registered as 2004 but Jaguar Marshalls have it listed and logged as a 2005 according to my chassis number. Work this one out anyone?
When ordering parts I have to make sure I state 2005 as according to Jaguar 2003-2004 models have different parts.


I found this out also with the amount of different front wheel knuckles made for the XJ X350. The ball-joint mounts are all set at different angles which affects the camber of said cars they are fitted too.


If anyone wants to see the differences I can post pics so others can work out which wheel knuckle fits their model. (in other words get your own knuckles shot-blasted and replace the ball-joints instead of buying new ones blind like I did.)


I also noticed another problem in all this.
When I replaced the battery after all work was done I have a problem with the radio.
I put in the code but this does nothing except bring up on screen a message saying "please wait".
It never gets any further than this.

 

An update on how I am going through the process ofelimination.

Partick The Cat, thank-you for the advice on the gasket pistonkit replacement.
The car has one height unit on passenger side rear lowerlateral arm front.
I never touched or looked at the rear as I was onlychanging the front shocks at present.

After removing the pump, which was located inside thebumper, behind the inner-wing insert on passenger front wheel I looked back andremembered the advice here.
Upon contemplation, the pump cannot be at fault assomeone else noticed the car is holding all other three wheels up at correct height.

I will therefore use a piston seal/gasket kit for thepump instead of buying a new one as this will save on cost plus since I have itout it would only be right to service it before connecting it back up.
I am doing this simply because the pump cannot be causingjust ONE side to drop so the fault lies else-where.
I say this because the entire pump has one single airoutlet, which goes to the Valve block in the boot and the valve unit also sendsair into the reserve tank.

Removing the front pump was very fiddly and awkward andwas much harder than me removing two complete air-shocks from the front andswapping them over. The time spent was obviously less on the pump but ease ofremoval is not easy owing to the suspended spring mounting set-up on theholding brackets of said pump. You have to be a contortionist to remove the 3mounting bolts on the brackets.

I now am tracing the entire pipe from the front driversside, through the entire car to the boot.

It is all pointing to a faulty valve in the air valveblock but as yet I do not know how to check this safely as I do not want tostart unsealing air pipes under pressure. I will think of something if no-one else can suggest how I could checkthem.

The images show my pump and location and the valve blockand reservoir in the boot.

The wires running to the battery are a charger as Ipunched in the wrong radio code and it can take up to two hours for it to clearthe message “Please Wait..” with the ignition on.

I have no fault lights that have come on in all theprocess of me rebuilding the front end. Nothing to say ride height is low orwrong or any other warnings.

 

I have got closer to the problem of why I'm down on one side on my suspension. Front drivers side.



At the beginning of the thread I said I heard an escape of air, which thinking back lasted for some seconds and was loud enough to be heard with the bonnet shut and me going to enter the driver’s side.



I have been following/chasing pipes all day to make sure each one relates to what I thought at the rear of the car in the boot where they locate in the valve block assembly.



All straight forward normally, but the two front airshock pipes on car are missing the colour coding on the tags or pipes in engine side. Hence I had to trace them back.

The one attached to the compressor is yellow, with a splash of yellow paint on the plastic. This is VERY wrong as the correct pipe is meant to be White colour-coded/tagged.

I worked this out by eliminating all the other pipes to the various outlets on the car.

I don't know which one of the two thicker diameter pipes which run to the front air-shocks is left or right yet but i'll know when I finally get the air system working again.

They are yellow and brown.


These two pipes are thicker than all others coming from the rear valve assembly. The air-compressor pump has a thin diameter pipe with white colour coding. (Yet someone stuck a dollop of yellow paint on the one in my car at the air-pump compressor assembly). This one comes from the Air-compressor to the rear boot valve unit.

The rear pipes are also thin diameter and go off in different direction inside boot to the tops of each air-shock.


When I released the brass nut holding in the pipe I expected to hear a lot of air escaping for some time.

I also expected the rear wheels to slowly drop as they are still sitting on their own weight with only the front suspended off the ground.

This is when it hit me what may have happened.

The air release was the pump as it has two outlets. The larger plastic outlet pipe with what looks like a fuel filter in line, probably a one-way valve was where the escaping air would have suddenly come from that I heard.

The actual reservoir tank in the rear of the car by this time was full of compressed air and has enough to hold the other three wheels at correct height even without the pump which is NOT working I suspect.

The valve block assembly keeps the pressurised air from returning, but as the pump failed, somehow air that escaped came from the front air shock through the pump outlet pipe.

So the valve block assembly failed on one valve, thus the air was free to escape under pressure from the front shock through the failed pump which let go. Or the pump is designed to allow this to happen when a valve fails.


I am about to open the pump so will hopefully see the piston is only worn and the bore is not damaged or scored, and if all perfect then the valve unit is the culprit.


Does this all make sense and does it sound like I’m on the right track?

 

This is the pump. I'll refurbish the rusty mounting bracket no problem.
Shows a serious water trap to do this amount of rusting considering it is meant to be hidden from the elements behind the bumper and also behind the wheel inner plastic wing.


I will try a new piston and seal, and take it from there.
By the time the kit arrives i'll have worked out which valve has failed although the unit is all one piece.

 

Here's my feedback:

Did you install a new olive on the air line? When replacing struts your supposed to trim a tad off the end of the air line so the olive has a new place on the airline to "grip" and hold the air line in place under pressure.

Sometimes you can get away with not cutting the air line, sometimes its necessary to do so. Specs call for the line to be cut when installing a new nut/olive (which probably came with the replacement strut)

Also, make sure the olive is installed correctly. Haven't done this in a while but you know its installed correctly when you cannot move the olive down on the air line once you have it in place.

You can leave the air line disconnected when starting the car. You should feel a steady stream of air when the front struts start to rise.

If you have no air coming out of the air line then your problem resides in the valve block in the trunk.

If you feel air coming out of that line then cut 1/4" off the air line square with a new razor on a block of wood. Use a new olive and don't over tighten the nut. Again, the olive does all the sealing, not the tightness of the nut.

I think you might have taken your compressor apart unnecessarily.

 

Thanks Abonano.
New olives and rubber seals and both pipes cut with a scalpel and sealed perfectly.
New shocks do not come with anything to fit as you have to buy everything separately if you are buying Bilstein. B3 and B4 models come bare, not even mounting nuts on the top mount bolts.
You have to buy the olives separate from Jaguar and also 4 new strut nuts as they are not even supplied by Shock maker.
I have checked both pipes/olives for air leaks as soon as I first fitted them as is normal in any air pipes being removed/refitted or replaced. I wish is what as simple as this.


The air let go from somewhere in the front.
The pipe from the drivers side I removed to see if I could feel any air when I turned the engine on but nothing.
I also don't remember ever hearing the air-pump running after I heard the loss of air so I better check the actual pump motor works.


The condition of the air-pump is very bad inside and I will post a pic soon of what I have found on the con-rod which is a large scoring all the way down one side of the con-rod, not the actual piston or barrel.


The pics of my pump are after I had to remove oxidized aluminium from the groove which holds the rubber seal.
The actual seal was/is caked in oxidized alloy and the two casings are very bad condition.


The images I have posted are after I started to clean up the mating surfaces so you will not see the real condition anymore.


I am going to try a new piston kit but I still suspect the pump is past it.
Tell me what you think when I post the pics of the mark right down one outer side of the con-rod, which means it has been forced against the side recently.


I think also the valve Block unit in the boot has a failed valve which would explain why no air can be felt at the front drivers pipe.


I will get a new valve assembly and swap it out as they are cheap compared to other parts on the Jag.

 

Try bagpipingandy again ... he may be able to supply more compressor bits, or do you an exchange.

 

Thanks all for helping me through this.
I have more to show.
The pump I have on this car has already been refurbished, which I never knew until I started taking the images to put on here.


You sometimes miss what is in front of your eyes.
Please try not to judge me for missing such a rooky error as I have slight brain problems and body problems but at least I worked out what is happening eventually.


The pump is now definitely getting changed, not a recon unit, i'll buy a new one.


I started taking images to show you here what I found when I opened the pump to check condition and on last image I suddenly noticed a sticker covered in spray paint and some bolts and nuts with over-spray.
Instantly then I knew this pump has been refurbished already.

 

I see what you mean about the connecting rod. I'd say that was there from manufacture; assuming they are initially cast then it looks like excess metal has been ground off ?

 

I have another question needing help.


Should I lift all four wheels off the ground to allow me to remove the rear boot control valve unit?
I ask because I believe when I start to disconnect the pipes the air-tank reservoir will lose all air and so will all the shocks.
I do know that air shocks should never be compressed with-out air in them as it can damage the bladder inside.


Am I right in thinking this?


Also when all this is done I still have to take it to my Jaguar dealer to allow them to use the computer to reset/check all the correct ride heights and also they need to do my tracking on all four wheels as the front cambers need setting up and the rear wheels as I have replaced all rear link-arms and bushes.


I am not in any hurry to get all this work finished because at the end of all this I will have a beautiful driving car that will feel like it just came off the production line even though it is 12 years old.

 

If you do lift all four wheels of the deck you need to have one end lifted with a 'cross beam' (there's a proper name for it, but I can't think of it at the mo') which is jacked with a single trolly jack in the middle. It's to ensure that you don't get any 'twist' on the body which could distort it.

 

There are two threads on jacking and air suspensions that may be useful to read:
https://www.jaguarforums.com/forum/x...points-161918/
https://www.jaguarforums.com/forum/x...acking-143073/

 

I asked a different question to what you have given me answers too.


I am asking will the suspension let go if I disconnect the air-lines which are attached to the valve block?


Hence if it is going to let go and release all air from the entire system then I will be better lifting the wheels off the ground to allow the suspension to hang down, thus not putting any pressure on the air-shocks.


I have now jacked all four wheels off the ground. My carer did one handle on the trolley jack and I do the other so we lift together. I have done this for some years when jacking cars as it gives me enough room underneath to work, instead of the car being up on one side only and you getting squashed as you get further under.


I have never in all my driving life used a supplied jack by the car maker on any vehicle as older cars would just crumple under the jack with rust and rot. So many cars in the 70's and 80's I saw wrecked with simply using the jacking points of certain cars, where the sill and floor would crumple.




I also have to say that Jaguar are talking CRAP about the mono-**** twisting if only one side is jacked.
I know they designed the car and built it but ask yourself one simple question, then you will see how stupid this statement actually is from Jaguar themselves.
This is a stupid written clause for Jaguar to get themselves out of any lawsuits from customers.


You jack your car up at the road-side or a breakdown truck jacks it up, simply to change a burst tyre, then in Jaguars own words or people in this forums beliefs, you CANNOT do this because you may twist the mono-****!!!


I don't care if people here decide to argue this point, I have no intensions of explaining how stupid this is and how stupid it sounds from the off-set.


This means every Jaguar x350 that has had a puncture has probably now got a twisted mono-****. Now can you see how stupid this statement and advice really is?


So every Jaguar X350 that has had a puncture has now been written off if this statement everyone believes is true.


I'll post some pics soon of the car safely off all four wheels.


MOT stations have for years used dual under-side jacks as this is easier and safer for the worker using them.
It also helps with making the entire front or rear easier to repair and also makes wheels and steering easier to move etc,. It has nothing to do with twisting bodies or mono-*****.
When you get into racing cars then you use full lifts as parts are titanium and carbon fibre which is a different kettle of fish to production mass produced cars.


Write or start your own thread if you want to argue about the jacking of cars. This is NOT what I asked or wanted to know in this thread.