Airmatic compressor working a lot but only after a longer (few minutes) stop.
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Member
Joined: May 2019
Posts: 111
Likes: 19
From: PL
'04 E55 Wagon
Airmatic compressor working a lot but only after a longer (few minutes) stop.
Hi.
I may have a problem with my Airmatic.
The suspension works as it should (damping/level control etc.).
The car sags like 1/3 inch max on all off the struts evenly in first few hours after shutting it off (actualy I measured an hour after and overnight) but then doesn't sag at all for at least 4-5 days (my record of not driving as it's a daily grocery getter).
I lost one of the compressor mounting springs and washers (long story). Replaced them temporarily with what I found on in the drawer, so ATM I actually hear and feel the Airmatic compressor working from the driver seat.
And now to the point. My compressor is working a lot each time when I start after a longer stop. I mean it does it each time I enter it and drive after it was parked but also after standing still for a long time with engine running for at least good few minutes (closed railway crossing with two trains to wait for etc.) and then It's working pretty long, for like a minute or maybe longer (of course It starts itself over 40km/h and stops below 20km/h - normal procedure to reduce noise in cabin). Funny is that when it'll finally stop (as mentioned at least a good minute of pumping) it's not swithing itself on when I drive the car without longer stops. Even when driving for a long time. Shorter stops (traffic lights) don't start the compressor too. So... When I drive around town, like from shop to shop etc. often switching the car off and getting out, the compressor is actually working all time/all day but as soon as I leave the town I can drive 200 kilometers without it swithing on. WTF??? Is this behaviour normal?
What I've checked/found/would like to know?:
- Found a few "compressor working all time" type of threads around the web. None of them had any clues.
- I can hear some valve tick/pop from time to time in the rear when I'm standing still (with engine running) for a long time (on a rail crossing/few minutes) - Is this normal?
- When I check all of the pressures in STAR (all struts/system/reservoir tank) they don't decrease at all in let's say 30 minute test. (didn't make a longer one yet)
- I've checked the pressures in all the struts. Then opened each damping and "extra volume" valve for at least 30 seconds on each strut. Then checked all the pressure levels again - no decrease.
- The compressor test goes ok - It gets to desired 14bar in a lot less than desired 40 seconds. (What part of the system is this test pressurizing? Feels that not the reservoir itself?)
- Once, but only once per past three months of driving I had a 5503 "Recovery time during filling of central reservoir is too long" error code.
- Are there no "leak tests" for Airmatic in STAR for W211? Reading about Airmatic I noticed such things in W220 related topics but I'm having only the "Compressor test" in my "Pneumatic tests" menu.
What made me suspicious:
- I'm having like around 10 bar pressure in the main tank when I check it with STAR - is this normal?
- When I read the GF32.22-P-4010E "Pressure supply, function" in WIS it says "The reservoir pressure is between 13 and 16 bar (at sea level)." Is my ~10bar when I stop the car and connect STAR too low then?
- When I'm in "pressurize reservoir tank" menu in STAR (where you can pump the reservoir tank manualy) I see that when I try to pump more than those 10bar it pumps the reservoir tank really slow or at least a lot lot slower than in the "14bar in 40sec.Compressor test mode" Is the "14bar/40sec. compressor test" pressurizing the reservoir itself or just the valve body (with the pressure sensor)?
- Actually I didn't try to get to 13 bar with manual reservoir pressurizing yet. Should I?
- I found that there is an option to show what's happening in the Airmatic system live on graphs in STAR but there's a lot of those options and they're all in German (part of developer mode?). Does anybody know which one is most handy for such an investigation?
So... Is it normal that the Arimatic compressor in the W211 works all time around town and I'm just paranoid because of my stiff/temporary compressor suspension/mounting hardware? If not, where to search more?
I may have a problem with my Airmatic.
The suspension works as it should (damping/level control etc.).
The car sags like 1/3 inch max on all off the struts evenly in first few hours after shutting it off (actualy I measured an hour after and overnight) but then doesn't sag at all for at least 4-5 days (my record of not driving as it's a daily grocery getter).
I lost one of the compressor mounting springs and washers (long story). Replaced them temporarily with what I found on in the drawer, so ATM I actually hear and feel the Airmatic compressor working from the driver seat.
And now to the point. My compressor is working a lot each time when I start after a longer stop. I mean it does it each time I enter it and drive after it was parked but also after standing still for a long time with engine running for at least good few minutes (closed railway crossing with two trains to wait for etc.) and then It's working pretty long, for like a minute or maybe longer (of course It starts itself over 40km/h and stops below 20km/h - normal procedure to reduce noise in cabin). Funny is that when it'll finally stop (as mentioned at least a good minute of pumping) it's not swithing itself on when I drive the car without longer stops. Even when driving for a long time. Shorter stops (traffic lights) don't start the compressor too. So... When I drive around town, like from shop to shop etc. often switching the car off and getting out, the compressor is actually working all time/all day but as soon as I leave the town I can drive 200 kilometers without it swithing on. WTF??? Is this behaviour normal?
What I've checked/found/would like to know?:
- Found a few "compressor working all time" type of threads around the web. None of them had any clues.
- I can hear some valve tick/pop from time to time in the rear when I'm standing still (with engine running) for a long time (on a rail crossing/few minutes) - Is this normal?
- When I check all of the pressures in STAR (all struts/system/reservoir tank) they don't decrease at all in let's say 30 minute test. (didn't make a longer one yet)
- I've checked the pressures in all the struts. Then opened each damping and "extra volume" valve for at least 30 seconds on each strut. Then checked all the pressure levels again - no decrease.
- The compressor test goes ok - It gets to desired 14bar in a lot less than desired 40 seconds. (What part of the system is this test pressurizing? Feels that not the reservoir itself?)
- Once, but only once per past three months of driving I had a 5503 "Recovery time during filling of central reservoir is too long" error code.
- Are there no "leak tests" for Airmatic in STAR for W211? Reading about Airmatic I noticed such things in W220 related topics but I'm having only the "Compressor test" in my "Pneumatic tests" menu.
What made me suspicious:
- I'm having like around 10 bar pressure in the main tank when I check it with STAR - is this normal?
- When I read the GF32.22-P-4010E "Pressure supply, function" in WIS it says "The reservoir pressure is between 13 and 16 bar (at sea level)." Is my ~10bar when I stop the car and connect STAR too low then?
- When I'm in "pressurize reservoir tank" menu in STAR (where you can pump the reservoir tank manualy) I see that when I try to pump more than those 10bar it pumps the reservoir tank really slow or at least a lot lot slower than in the "14bar in 40sec.Compressor test mode" Is the "14bar/40sec. compressor test" pressurizing the reservoir itself or just the valve body (with the pressure sensor)?
- Actually I didn't try to get to 13 bar with manual reservoir pressurizing yet. Should I?
- I found that there is an option to show what's happening in the Airmatic system live on graphs in STAR but there's a lot of those options and they're all in German (part of developer mode?). Does anybody know which one is most handy for such an investigation?
So... Is it normal that the Arimatic compressor in the W211 works all time around town and I'm just paranoid because of my stiff/temporary compressor suspension/mounting hardware? If not, where to search more?
Last edited by coobah; Nov 9, 2019 at 07:26 PM.
Member
Joined: Jul 2017
Posts: 126
Likes: 22
From: Dubai
2005 E55 AMG Wagon
I recently had the rear air suspension replaced and during my time at the garage, they did the compressor test and I did get the error 5503 "Recovery time during filling of central reservoir is too long"
To be sure of the leak, we checked it thoroughly from the compressor to the rear suspension and there were no leaks. The fix was a pretty simple one on my car. I bought the Airmatic compressor filter and changed it. The rubber pipe connecting the compressor to the filter was deteriorated and that was replaced too. Looks like that rubber tube is where the leak was. The compressor performs better in the test via star. No more error 5503.
The parts were pretty cheap. The filter was about $20 and the rubber pipe $7.
Thanks to a thread here on MBworld that helped me knowing that the compressor had a filter that could be replaced and the rubber piping could be a point of leak.
To be sure of the leak, we checked it thoroughly from the compressor to the rear suspension and there were no leaks. The fix was a pretty simple one on my car. I bought the Airmatic compressor filter and changed it. The rubber pipe connecting the compressor to the filter was deteriorated and that was replaced too. Looks like that rubber tube is where the leak was. The compressor performs better in the test via star. No more error 5503.
The parts were pretty cheap. The filter was about $20 and the rubber pipe $7.
Thanks to a thread here on MBworld that helped me knowing that the compressor had a filter that could be replaced and the rubber piping could be a point of leak.
