Reptar0nIce

Hey all, so I'm having some Airmatic issues with my 2005 E55. Today when I went out to the car I got a warning that it was too low. Turns out over night the front had dropped significantly (basically bottomed out). The rears seems to be at the correct height. I tried hitting the lift button, and didn't hear the compressor fire on. I've tested the compressor and confirmed it does work (applied 12v directly to it). Next I'm going to test the relay. And no fuses are blown. What I can't figure out is why would the front drop overnight if the compressor stopped working, and why is the rear still at normal ride height?

coupesedan

Valve block?

Any stupid behavior in an air suspension system is usually the valve block.

Reptar0nIce

Thanks, I'll take a look at that. Could that also be causing the issue with the pump not turning on at all?

Reptar0nIce

Now I'm not sure where to test next. I've pulled the relay, and tested it by supplying 12v to it, then testing resistance on the circuit, and it's showing that the relay appears to be good... I'm contemplating driving 45 minutes to get a new one from the Merc dealer, but now I'm second guessing that...

Reptar0nIce

Rapid fire posts, I know, but now I'm completely baffled... I reinstalled the air pump, put the original relay back in, and now I can get the pump to turn on! My battery is pretty dead from all the testing, but it now turns on, and was able to raise the drivers side front a little. I have it on a charger now, so we'll see. The battery died when I was replacing the driveshaft center bearing, I left the key in while the shifter was in neutral. Anyone run into any issues where a dead battery can cause the problems I've had?

cfmistry

A dead battery will not cause the front to drop. You have a leak somewhere - likely in one of your front struts. Look closely, is one side lower than the other? That is usually the blown side.

Ls1toAMG

Interesting enough the back does not level sides independently like the front does . The front senses both sides individually the back has one level sensor if a bag is bad it won't be level. So I would say you leak it to the front area before the shocks and sensors

Reptar0nIce

So it looks like the passenger side is lower, I might have a leak there? I'll try to listen for a leak. With the compressor not working it was hard to tell.

cfmistry

You can spray some soapy water on there and look for bubbles once the compressor is running. But my money is on that strut being blown.

Reptar0nIce

yep, I’m thinking it’s a blown strut now too. When I turn the car off after using the lift button I can hear some air escaping the passenger side. Bummer! Another thing after dealing with the center drive shaft bearing (turns out there are two sizes).

Yuille36

Last March, I had the same issue blown front strut. The car would raise then drop, when raising. I had the system tested by the tech, and he was prepared to replace it.
I told him to replace both front struts, as they should always be replaced in pairs. Where the logic is just replacing one, when you still have a old strut on the other side just waiting to collapse later down the road.