I also have an airmatic problem. All four wheels are down. All four.

I found the pump near the rear wheel on the drivers side.

Questions:

1.Is this pump for all four wheels?


2. If so would it be fair to say that the pump has failed? (The car rising signal on the dash comes on but nothing happens; I hear a soft hissing sound from the pump i located but car doesn't rise anywhere)

Thanks,

PS I do realize from reading the posts that I may have a leak on the front struts that may have caused the pump to fail in the first place.

 

the suspension pump is in the front of the car in front of the right front wheel behind the bumper. you should hear it running when the suspension up button is pressed.

 

w220? If so under the front RH fender behind the wheelarch protective liner. Access from under the car. Move part of the undershield.

I suspect the other "pump" that you have found is the PSE which operates the security / doors.

Pump controls all four struts thru a valve block connected to the pump.

Easy to see if the pump is OK. Disconnect main power lead from the pump (heavy cables) and power up directly.
Does the pump run?
Does the pump lift the car after about 30 / 40 secs?
Does the car sink again after the power is turned off?
Can you hear an air leak from the pump, tubing, valve block or strut topsafter the car has been lifted and when the pump is off? All should be quiet.

Stuart.

 

Your right. I was looking at the wrong pump.

The car doesn't lift at all and it doesn't sound like any pump is running but I'll take the wheel off and test it as you suggested. Hopefully later today. I assume the right front is the passenger side.

 

yes correct

 

OK I found the suspension pump. I hooked up a battery charger to it and the motor runs but the car doesn't rise. I tried it with the car engine on also and the car didn't rise. This could mean that its not pumping out air but I don't know how to check it. How can I check it?


I also checked for voltage on the plug side because I was wondering why it wasn't running with the plug connected to the compressor. There was no voltage going to the compressor with the car on. I checked the fuse and the 40 amp fuse was blown. I replaced the 40 amp fuse and still there is not power going to the plug. I checked the fuse again and its not blown but power is still not going to the compressor. Why isn't 12 volts going to the compressor? Even if the compressor is not pumping out air it should still be on when connected to the plug, shouldn't it?

Now I'm even more confused???????


Dom

 

Mmmm.

Tell me more about the history on this problem. When, how did this problem start?

OK the pump runs. However dependent upon the type of charger you used it may not have supplied sufficient power to run the motor at full speed / power.
Next step is to determine the pressure of the air in the line coming out of the pump / reservoir. No pressure = no lift = dead compressor rather than motor. There is a one way valve inside the compressor that wears out.

No power to the compressor?

Surprising that the pump / compressor is dead AS WELL as no supply and that the fuse has also blown. Why did the fuse blow if the pump works OK. Something not quite right here which is why I have asked for history. Did this car go wrong whilst you owned it or have you bought a wreck or similar. If so ANYTHING (and everything) could be wrong!!

Dependent upon your skills tracing a fault in the control system of the compressor is not a simple task. Best get the codes read by an MB dealer which will pinpoint the exact cause.

The usual scenario is a pump that has worn out because it is working too hard in order to stem a leak in the system which is usually located in the suspension strut top mounts.
Lots of posts about this.
New struts are mega money although a repair kit is available for the top mount.

Stuart

 

I've had the car since 2000. Last Friday my wife said the airmatic waring came on. She pulled over and read the manual. She used the manual ride height adjustment and the waring went away and then she came home. She told me about it that evening and the next morning the car was down on all fours.

The fuse was blown. I've read on this site and others that this is a sign of a bad compressor and that relay goes out along with the compressor and fuse, although I don't know why this is. This may explain why there is no power going to the compressor.

I found the compressor and relay for 350 dollars and I think I should try that. It would cost that just to have it diagnosed by a dealer. What do you think?

Dom

 

I replaced the compressor and solinoid today and everything works. Car is up on all fours.

Now how do I figure out if I have a slow leak?

How can I see if the top of my front struts is leaking?

Dom

 

Just seen that you also have the engine code problems.

Not sure that I can add much more. I sense something is missing or something wrong in my understanding of what you have advised.

IF as you say the airmatic compressor works fine when connected direct to a power source but doesn't lift the car then I'm confused.

It is extremely unlikely that multiple problems would occur at the same time. i.e. fuse blown, relay not functioning, compressor not running whilst also failing the supply air.

Compressors do go wrong but on the data you have provided it wouldn't be at the top of my list.

The key I suspect is why the main 40a fuse has blown. This could well indicate a bad compressor BUT that doesn't fit with compressor runs fine on charger BUT doesn't lift the car.
Stuart

Likewise with your engine codes.

Sensor 1 O2 readings should range from approx 0.1v to 0.8v and have a consistent wavelength cycling approx every 1 sec / 2 secs.

Sensor 2 O2 reading should be much closer to zero. This is the O2 level after the pre (main) cat has done its work and O2 level should be low (used up if the cat is working correctly)

However the codes show problems with Sensor1 Bank1 so something would appear to be wrong with the data that you have provided.

If you don't have the means of looking at the O2 sensor waveform than I guess changing the O2 sensor(s) is the next logical step.

Stuart
Stuart