dillon37

I have replaced all control arms and suspension bushings as well as the lower ball joint on front right of my 2001 W220
Air-matic was working perfectly b4 i did the job
since, air-matic will not fully rise on right side
I got an answer to this question here b4
saying don't torque the control arms till put tire back on and start car to let rise
that did not work
paid $130.00 to have it diagnosed shop says I now need a new compressor and relay and a level line
I don't know what a level line is
How is this possible that suspension air compressor is bad when three sides are up only the front left is down?

thanks in advance

mercy-me

Can you get more information on "level line"?

If you the car is raising and lowering on three corners then your compressor is not bad. You can hear the compressor run at start up and you can watch as the car seeks its level. Hard to imagine doing suspension work would cause the strut to fail alone. Exercise the "Raise and Lower" switch on the dash to observe the leveling and hear the compressor run.

I would recheck all connections to the sensor. Something got disturbed when you did the lower ball joint.

Is your "Indy" shop familiar with MB's and do they have a proper diagnostic system ie SDS ??

Good Luck,

Bob

cybertronicify

You should check the valve block and the level sensor for the strut that is down. The valve block is right next to the compressor. Just follow the pressure line from the compressor and you will see the valve block. Sometimes if one of the valves on the block fails, your strut will be down.

BTW if you still have a SIEMENS or TYCO or BOSCH relay in your fuse box, you should replace it with a HELLA relay. My TYCO relay killed my compressor couple days ago, it latched on and stayed on. HELLA's have a much lower failure rate.

dillon37

yes they are an indy shop and work on MB and other euro cars too
Is there a schematic available online that details the air-suspension system for w220 ie repair manuel?
I have the hella relay and will go to work on it again this weekend

wallyp

Short answer: If the shop went thru the full diagnostic testing on the compressor, then yes, it is possible for the compressor to fail one or more of the diagnostic tests and still lift three of the struts.


Long answer: My first suspicion is that there is a problem with the level sensor or its linkage. That can cause that corner to be low, if the faulty sensor reading makes the computer think that the strut is at the proper height when it isn't.
There are several tests that the compressor must pass to avoid an error flag. One is that it must generate a specific high pressure. If the piston ring is worn, the compressor cannot achieve that high pressure. Another test is the time required to pump from a specified low pressure to a specified high pressure. Again, if the piston ring is worn, it will take too long to achieve the high pressure, and an error flag will be set. If the problem is a worn piston ring, it can be replaced fairly easily for about $25. There are several YouTube videos on replacing the piston ring. I would suggest replacing the compressor inlet air filter and checking the desiccant in the compressor at the same time.


Remember that we are all making long-distance guesses, based upon very little info...

lganski

It almost sounds like the sensor was not hooked up or done improperly.