hi i'm new in this forum and have owned S class benz for years so after getting the shaft by the mechanics i've decided to get into the self diagnosing mode myself. i'm having a problem with frequent harsh rides although i've changed 3 out of 4 airmatic struts including the valve air block. there are no airmatic low reading on the dashboard although everytime i press the unlock button the rear sagging struts rise up to the proper level. mechanics have told me that one of the rear struts is causing both of the sides to slowly deflate but the reservoir kicks in and rises the car back up again which is refilled by the compressor. a pneumatic system must be leak proof so for it to sag there must be a leak somewhere and some of the mechanics told me that the old soap test is no good because it could actually be the rear lines. the valve air block is ruled out due to a replacement of a genuine mercedes new air block a few months ago. i feel like the ride is harsher than it normally should be because when i go over the railroad crossings i feel it more than i should. and then another problems is that my steering gets hard as i come to a stop but the mechanic said that i don't have a power steering problem at all and none of my check engine light or abs or airmatic light come on. now a mechanic said that my problems are intertwined due to a problem in the airmatic system or the wheel speed sensor it affects the ride and the steering feel. i don't know what to go with and i would like my car to float like it should. does the wheel speed sensor have control over the airmatic dampening and the power steering feel? and btw when the mechanics hooked up the airmatic struts they never programmed it to the car and they claimed it's a simple plug and play and doesn't have to be programmed to the car while other mechanics claim it must be programmed. please let me know anyone. thank you so much guys.

 

Tariq, I am not in a better position to determine what the problem is than the technicians who can actually look at the problem. If you have not done so, I suggest that you have Mercedes diagnostics run on the system. I am sorry I cannot do more.

 

hey skylaw my main question is that if there's a link between the wheel speed sensor and airmatic ride control and also does it control the stiffness of the steering wheel at different speed

 

A bad wheel speed sensor can be linked to stiffness of steering, but the only way it would affect airmatic is if you set the car to rise, and a sensor indicated you were traveling faster than 55 mph - which is when it would lower. However, travel is only ¾ of an inch; that would not cause the rear sagging.

Please see the links immediately below the heading "Both Airmatic and ABC" at https://www.benzworld.org/forums/w22...ml#post4298889 (you will need to scroll down the page a bit) - it starts out "ABS, BAS and ESP Warning and difficult steering..."

Sagging in the rear is either a leak, as has been suggested, or bad input from the rear ride height sensor (sometimes from something so simple as a disconnected link on the sensor).

 

hey skylaw it sags more on the left side on the rear than the right but the replacement struts i bought in pair for the rear strut replacement the mechanic installed them wrong. he lowered the car on the bellows before charging up the air pressure to 5 bar and i heard the right side of the new replacement pop and then my valve air block gave out too. so i replaced the one that popped on the rear right side with an exchange strut but the one i didnt change on the rear right is the one sagging and i think his wrong method probably caused a minor leak because i also replaced the valve air block so those are the ruled out things. the only thing i didn't change is the rear ride height sensor and replace the strut on the left rear that was installed not according to the guidelines of keeping the car on a lift to charge up the strut and then slowly drop and keep in mind that was also a new strut. i changed the struts in pair because the labor is cheaper together than individual ones twice. every time i come out the house the car is sagged fully on the left rear side but not fully on the right rear one. i wonder if the rear left leak in the bellow is causing the right one to lower too. and also whenever i wake the car with the unlock button the car raises up to proper ride level everytime but i don't wanna burn out my compressor. i wanna consult u about my method of process of elimination that since i've fixed many parts of the airmatic the ones i didn't replace is the airmatic air line and the ride level sensor front or rear and the rear right strut wasn't installed according the Mb guidelines. and also are these struts plug and play or they need to be programmed to the car? please let me know what you think. thank u very much for ur time and patience.