Left rear has been at times a bit low since I bought the '03 E500 last year. Today I found the leak...the connector on the compressor that leads to the valve block. Gently tightened the fitting made it worse. Now it's really leaking. What to do? Is there official MB fix available at dealer parts?

Better yet, is there an unofficial fix someone can recommend until I get back across the border into San Diego?

Glad there's food in the house.

 

Tightening it was likely a bad move, as you may have stripped the threads in the compressor housing. The connector needs to be no more than finger tight + a smidge. If you remove the brass connector you should see a o-ring which seals it to the compresor housing. The other o-ring, seals the air line passing thru.

Also, for that to be cause of your left rear dropping... means the valve body is suspect. Either one or multiple solenoids are stuck open OR there's an electrical fault causing that solenoid to stay open.

 

Roger that. Was able to find another 'O' ring and stopped the leak. Mine has only one 'O' ring unless you refer to the brass compression fitting that sits on the line between the voss and female compressor end. Headed to civilization to pick up a replacement voss, filter, and compressor rebuild kit.

Thanks for your help.

 

Hi Overheated---I'm having the same exact issue on my car which I've had for 15 yrs. Same rear driver's side. Could you tell me more info or have a pic of the connector at the compressor. I can't figure or find my issue. I've even cheanged up the airbag twice, changed the valve block and still every morning I have a car sitting on its ***!!!!

 

I trust you have a scanner. The fitting is a Voss #4 male connector that is the only white nylon line exiting the compressor going to the valve block. These connectors are used throughout the system. See attached. The male fitting is brass, the female on the compressor itself is plastic.

The LR has always been low. At the point the LR sank too far, I soapy tested all lines, tanks, connections, bags, ad nauseum, and found the leaking fitting. It threw a code. The female section was stripped. Horrible design.

I was able to secure a new brass fitting and O ring, I installed it. It still leaked. It soon popped out. The car went flat. Permatex/Locktite 242'd it. Pinned it secure. Cured it overnight. Code erased. Stopped leak. The car raises and holds.

Pumping only 8-9 BAR. Should be 12+ according to Arnott. I need a compressor. I was asked to check the pressure release valves on the compressor. There are two. They go by a number of aka's. One is held in place by two torx bolts. The other unscrews. The car raises and holds.

The LR is two fingers from the top of it's tire. The RR three. The car raises and holds.

I understand from advice here, my mechanic, and Arnott...an airbag will drop a single corner, but the rest of the car will stay up. A leaking airbag may not be able to be seen when tested with soapy water as the bellows may on some models be covered with a sleeve. No code.

A solenoid in the strut will sometimes stick open dropping that corner - a code will appear, but not always.

So we surmised that since there is now no leak, the listing corner may be due to either the weak pump, or calibration. The car raises and holds.

The system should be tested with the engine running, the car set to raise, and the suspension set to II.

 

Great info, I need to try some of that. Lucky for me, after 15 seconds after I start the car, it goes right up and lasts thorughout the day. But you know, that feeling when you first see the car in the morning, flat on the ground, only on the rear drivers side. I hate it!! PS--I dont have a scanner.

THANKS!!!

 

Lucky for now, till the compressor kicks the bucket…

Rear air springs are super common and should be replaced in age, regardless. It’ll save time troubleshooting later. As noted impossible to check, since they usually leak from the crimp which is under a fold in the bladder.

Obly way to check is removing them and the protective boot and inspecting… at which point they should be replaced for the effort involved.