hey guys
i have a 2004 XJ8 all of a sudden the back of my car is lifter so high what can i do -all ive done was disconnect the battery and it still way high in the back -please help me
dave della

PS 2 days ago it looked a bit low-then a day later it went so high-im cinfussed
ty guys

 

Hi Dave,

I'm still learning about the air suspension system myself, but I know that others have had problems similar to yours.

Did anything unusual happen just prior to the rear suspension raising up? For example, did you raise the rear end with a jack? Did you carry a heavy load in the trunk? Did you remove the spare tire/wheel from the trunk? Did you hit an especially bad pothole or obstacle in the road?

Just thinking out loud:

There are two height sensors at the rear end - one on each side. It seems unlikely that both sensors would malfunction at the same time.

The pressure in the air shocks is controlled by the valve block, which is next to the air reservoir tank in the trunk. It seems unlikely that the valves for both rear shocks would malfunction at the same time.

If the exhaust valve on the compressor were siezed closed, I would expect the front end to be high also.

I'm wondering if, for some reason, the air suspension control module is confused and believes it needs to raise the rear end to level the car.

It would be helpful to know if any Diagnostic Trouble Codes (DTCs) have been stored in the computer. Do you have a means of reading the Jaguar-specific codes yourself? If not, it may be worth paying a good independent Jaguar mechanic or dealer to read any stored codes to help point you in the right direction.

Hopefully others will add their thoughts and suggestions.

Please keep us informed.

Cheers,

Don

 

ty don no i diddnt do any of the points u said-im bringing to a jaguar guy tommorow and he said hes gonna put the computer on it he said something about a height control vale-maybe another name for what your sayin-my wife said today that the front seems a bit higher but riding it today the front felt fine -the back forget it it was like my 69 firebird with air shocks -lol-bumpy as hell -the front felt fine-so in the trunk(ive seen something under the spare tire once before about a year ago-i diddnt touch nothin -can you do the old italian way and tap the vale block and could it free up or now u said the front lifted is makin me wonder if its the block piece you are talkin about-i hope to know more tommorow after this guy looks at it-but i cant thank you enough for all the input you just gave -if anything i said here gives you as u said thinking out loud-im all ears -again ty so so much-im hoping this isnt a major job
PS when i firt got the car 3yrs ago under warranty i had a new air compresser in driver side fenderwell replaced along with the LF shock replaced -it had a leak and all has been fine till just this also when you say 2 sensors in rear end -do you mean under car or under spare??

 

Hi Dave,

The height sensors are mounted in the suspension under the car, inside the wheel wells. On the rear there are two sensors, one on each side of the car. On the front, the earliest X350 cars had two sensors, but from MY 2004 onward the right front sensor was eliminated, so most of our cars have a front sensor only on the left side.

Cheers,

Don

 

If you have no fault message and codes, it suggests the system thinks the rear height is correct, pointing to a height sensors and/or height calibration issue.

 

hey guys ty much for all in put-went to my guy no cades at all-his machinre had something to deflat front and rear susspension bags-we did -it looked like a low rider for a day then it started lifing again-now 2 days later back to the same-we are goin try it again today and he is so busy we are goin to deflate and then in a day when it gets to normal height-remove the air susspension fuse and see if it stays at that height untill he can get to it next week-is there a way to deflate the bags without me goin back to him if it goes up again and using his machine-if there is a way ill do it untill he can get to it-he says he has to spend more time with it -but guys you are the best for givin me all the advise-he said its most likely a sensor also agin if there is a way to deflate them without a machine that would help
dave della

 

hey guys
on a 2004 XJ8-is there a way to deflate the rear airbags without using the machine that does it-im waiting for my mechanic to get time to repair it and im willing to deflate them untill he can get to it
ty again all for all the help

dave della

 

Hi Dave,

I believe you could at least partially deflate the rear struts by carefully loosening the brass fitting for the air hose on the top of each strut. Loosen the fitting just until you hear air begin to escape, then allow the air to escape slowly until the strut height is where you want it, then retighten the nut. Our fellow forum member abonano cautions that many owners and mechanics have overtightened the nuts, damaging the air hose and compression rings and causing leaks. He suggest that the nut should be tightened only about 1/4 turn past hand tight.

Just to be sure I understand the malfunction, your mechanic deflated all four air bags, you drove the car for a couple of days, and now the rear end is too high again? And both rear struts are too high, not just one?

Don

 

yes both are high again and the front seems to b ok --ty for the help and anymore would also help
also i just went to look to see where the line goes in and from under the car i cant see it-are they under the carpet in trunk or remove the wheelwell covers -i cant see the air line

ps
isnt there a junction block somewhere that the lines go to??

 

ok guys-we went and took all the air out of the airbags AGAIN now it says vehical to low-will they fill up -cause last time we did this -in 2 days it got back to where all the problems started-i hope it will start lifting and then pull out the fuse till he can get to it-ty for watching my posts and answering them-this forum is AWESOME

dave

 

Hi Dave,

Great question! Yes, there is a valve block where all the air shock air lines connect - it's in the trunk near the air reservoir - remove your spare tire for access. The hoses are color coded and the Workshop manual tells you which color goes with which strut. Also, the rear air hoses are a different size than the fronts, but I can't remember which are 6mm and which are 4mm. The manual will tell you, or search this forum because I know that information has been reported by knowledgeable members. I'd look it up for you but I have to run. I'll check back later tonight.

Cheers,

Don

 

thanks guys now i had the bags deflated again and now vehical to low is on and car is low-will it take a bit b4 it fills-i know the compresser works cause it filled it back up in 2 days after i deflated them 3 days ago
you guys are grear t
ty again
dave

 

thanks don
realy thanks

 

hey guys
on a 2004 XJ8 with a 4.2 engin
what kind of transmission fluid does it use-goin to have it checked and in case in needs some i want to have it ready
thank youu
dave

 

Hi Dave,

It's best to start a new thread when you change the subject to help keep the forum better organized and to attract replies from members who may know a lot about transmission fluid but nothing about air suspensions, so they'll never even see your question.

Even better than starting a new thread is searching the forum for previous threads on any given subject. I believe you will find that for the ZF 6HP26 transmission, the recommended fluid is ZF Lifeguard 6, but opinions vary regarding other alternatives, so check the information already available by using the forum search function.

Cheers, Don

 

don b
i found1 of the fittings that lets the pass air bag out its the smaller of the 2-so its red tape-no other is red but your sayin that the other one that is the same size wrench would be the oter side-?
also where would i find the worsop manual-i have the owners manual and 2 different cd"s for my car-can u lead me to the workshop manual
thanks guys and ty don
dave

 

Hi Dave!

I'm not sure about the color coding of those hoses but I have read that they are each color coded so I'm sure you're right that the other one of the same size is for the other side. I believe there is a schematic for the air suspension showing the color codes in the Workshop Manual. Below are the links where you can download the manual in six sections. I copied these links from the X350 'HOW TO' quick links thread on the home page of this X350 forum:

http://www.mediafire.com/download/md...f+contents.pdf

http://www.mediafire.com/download/aa...nformation.pdf

http://www.mediafire.com/download/n3...2.+Chassis.pdf

http://www.mediafire.com/download/9b...Powertrain.pdf

http://www.mediafire.com/download/0i...Electrical.pdf

http://www.mediafire.com/download/4j...+and+Paint.pdf


Let me know if you can't find a schematic for the air suspension hoses and I'll look through another document I have in printed form.

Cheers,

Don

 

Info from the work manual:

 

wow don u are the best -im goin out now to try the left one-im glad i can do this so i can at least drive the car-my mechanic hopes this week we can figure out which sensor it is so i dont have to keep doin this but i dont know how to thank you for all the great help that u have given me-have a safe and fun holiday weekend and ill get back to you soon
dave

 

hey don -its me again -ok now what happened is i took out the 10amp fuse in trunk that said just air susspension-well the whole car dropped front and rear and now it will not go up-any ideasi have an appt on thurs with my mecheanic-but he said to bring it in once it gets high in the back so he can go from the original problem-anyway of manualy filling up the shocks-and once again thanks for all the help
dave d
ps can i put air in that valve in the trunck to lift the car?????