Colts19

Hello..This is my first post, but I have learned much from these forums over the years and saved a lot of money, and I thank everyone on these forums for that..

Okay, my problem...2 1/2 years ago and 20,000 miles ago I had the front struts seals repaired and a new compressor installed...and that fixed the problem..

In the last couple of weeks, I will go out in the morning and the back will be low or completely down and the front will be fine....After starting the car it will rise to normal levels....Then the next day I will come out and the Front will be lower or completely down, and some days both front and back will be lower or completely down...I don't hear any hissing from a leak...and when I start the engine the pump will run, air up and shut off..and after I drive the car and shut off, you can hear the release of air and it stops..What would cause different struts at different times to be lowered? ..Any ideas will be appreciated !! thanks...

jessfaust

I have the same prob now. A month ago I replaced the compressor motor. Just the other day it showed "STOP Car too low" again. WHen I reached home the Front driver strut is way all the way up, the front pass seems normal but my rear pass side is down all the way even pressing the manual lift switch it doesnt lift at all. The front still remain high and wont lower down at all. I'm guessing the suspension valve on top of the comp motor may not giving the right amount of air to every strut. Planning to replace the valve.... ANY HELP PLEASE!!!!!

Colts19

Jessfaust,

To sum it up...I replaced the control valve and it solved my problem... You can order it online and find and independent to replace for you much cheaper then the Stealers will do it for.. ..It could be just a lose line at the top of the control valve, but if that's the case it was probably caused by something faulty in the control valve...Don't know your mileage, but if the control valve has never been replaced, do it....It should fix your problems... From what I have read the rear struts don't normally fail. I had my front struts and compressor replaced before the this happened, so I was confident is was the control valve when my front one day was lower, and the next day my back was lower, that says it all, control valve..
Hope that helps!

Colts19

Call Mike a Skyland Automotive to order the part... A Mercedes dealer in NC...ask for Mike... 800-849-2765.. You will not do any better anywhere. OEM parts at a great price from a dealer.

wallyp

I have also had good service and prices from Skyland.

I also had a rear strut fail - just a slow leak that would drop the left rear overnight. Replaced that strut with a rebuilt from Arnott, problem solved.

I now get an occasional Fault Message telling me that there is an Airmatic failure, and that I should visit the workshop. I checked the codes with my Star System, and the stored code said that the output pressure of the compressor was low. I'll replace the compressor eventually...

jessfaust

Colts19,
Thnx for the response..I did replace the suspension valve $291. I replaced already the compressor months ago...The problem did not go away. Used soap water spray and confirmed no leak everywhere except the rear struts ( Dont know where is the access for trhe rear struts). If I press the lift switch, the whole car will rise but the four wheels are not leveled to each other. Driver front is all the way up, driver rear is normal, pass front is normal, and the pass rear is way way down.

wallyp

Access to the rear strut connectors is at the corners of the shelf behind the rear seat, just under the rear window. There are triangular covers that just pop off.

The problem could be that the driver front is too high, but is just as likely to be that the passenger rear strut is low. Not very likely that both are faulty. If you can get access to DAS, it will tell you the pressure in each of the struts.

jessfaust

Is the access inside the trunk? do i have to remove the back seat cover?
How about my driver front strut. Its all the way up. Cant release any air from the strut.
Whats DAS?

Thnx Wallyp

wallyp

No. No. If your car is the same as my 2003 S430, all you do is to get in the rear seat, turn around, and pop the cover off.

Do you mean that if you disconnect the air line on the top of the strut, no air comes out?

DAS is the computer diagnostic system that allows you to diagnose and adjust the car thru the on-board computers that run the car. The dealers and many independent MB shops will have such a system. You can put together your own system for somewhere between $500 and $1000...

jessfaust

Wally,
My apology I did not specify my car model its 2002 S430. I dont see the triangular part that pops up in my car.
Regarding disconnecting the line on top of the strut..I tried that on the two front strut and no air came out. Maybe there is a chk valve inside the strut..no idea really..

jessfaust

Colts19,
Do you know the access point on 2002 S500/430 rear strut where the air line from the compressor connects to the top of the strut. Just like the front struts that you can see already. Need to check if the air is pumping the rear strut. Thnx...

wallyp

Perhaps your 2002 is not the same as my 2003 - but I thought that they were the same.

Walk out to your car, stand just behind a rear wheel. Look down thru the rear window and find the rear headrest. Look just toward the outside of the car from the headrest - is there a visible line on the flat surface, outlining a 5"x6" panel that is shaped a little like a fat triangle? If so, that is the access panel for the top of the rear strut.

jessfaust

Wally,
I finally found the fat triangle you are talking about. I just thought at first that those are the speakers. Just fried it out using my finger n showed the airline to the strut. Haven't check the air yet at least I know now...A big thnx..

Jessie