Air suspension, not raising vehicle in rear.

[endstu]

so, i have a mercedes benz w211 e320, 2007 mod.
Air suspension is not working correctly.
I find no fault codes, and have replaced rear suspension and compressor.
I hear the compressor working, and i know it sucks in air. But vehicle does not rais it self.
Sometimes it works, sometimes not.
Pressure is 5-6 bar.
And i have connection to all sensors.
Lock position off.
Vehicle level is 0 mm in the front, and -60mm in the rear.
Where do i start? Anyone had the same problems?

Im almost giving up. Please help!
Thanks in advance.

 

[Wearsthefoxhat]

Has it ever lifted up since replacing the rear suspension ? Have you changed the relay in the front fuse box ? The lead to the compressor, not the power one can get damaged, rubs on chassis.. as can the cable to the rear sensor…

 

[endstu]

Has it ever lifted up since replacing the rear suspension ? Have you changed the relay in the front fuse box ? The lead to the compressor, not the power one can get damaged, rubs on chassis.. as can the cable to the rear sensor…

It lifts sometimes a luttle bit. I changed relay that followed when i changed compressor.
What power can get damaged you mean?
Power relay?

 

[Jobsworth]

there is only one level sensor on the rear. It’s in the middle, above the differential. Check the operating arm hasn’t rusted away. I’ve seen that before

 

[Wearsthefoxhat]

The problem could be with the valve block above the compressor. Moisture ingress causing valves to stick. What was the condition of the air inlet and filter to the compressor.

 

[endstu]

there is only one level sensor on the rear. It’s in the middle, above the differential. Check the operating arm hasn’t rusted away. I’ve seen that before

You mean this? Thats behind the differential

 

[endstu]

The problem could be with the valve block above the compressor. Moisture ingress causing valves to stick. What was the condition of the air inlet and filter to the compressor.

Don’t know the condition of the filter.. is the valve block on the compressor? Because i changed the whole thing to brand new

 

[endstu]

The problem could be with the valve block above the compressor. Moisture ingress causing valves to stick. What was the condition of the air inlet and filter to the compressor.

As you see, its brand new. The whole unit

 

[endstu]

there is only one level sensor on the rear. It’s in the middle, above the differential. Check the operating arm hasn’t rusted away. I’ve seen that before

I checked a little on the car, but did not find anything obvious under.
I see that the air line goes inside the car, so i can’t check for leaks longer in on the line.