Is this normal for Airmatic operation?
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From: Allentown, PA
'08 GL 320 CDI
Is this normal for Airmatic operation?
I have air struts, w/o ADS (if it matters for this question).
I just replaced the front, right air strut. I've noticed that when I'm driving around, I can hear the compressor come on every once in a while. Is this normal operation for the system? Am I just being overly sensitive because I just worked on that part? Granted, I could have another leak somewhere, but the truck, at this points, stays inflated at all four corners overnight and I don't hear the compressor ever come on when I'm in Park (with engine on).
I just replaced the front, right air strut. I've noticed that when I'm driving around, I can hear the compressor come on every once in a while. Is this normal operation for the system? Am I just being overly sensitive because I just worked on that part? Granted, I could have another leak somewhere, but the truck, at this points, stays inflated at all four corners overnight and I don't hear the compressor ever come on when I'm in Park (with engine on).
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From: Allentown, PA
'08 GL 320 CDI
I bought an Arnott. I didn't do a soapy water test (on the other bags, too), yet, but will.
Is there a way to definitively test the system at a dealer with the STAR system (or similar)? Admittedly I could be assuming/guessing, but I thought it was still possibly a hard thing to diagnose unless it was REALLY acting up?
Is there a way to definitively test the system at a dealer with the STAR system (or similar)? Admittedly I could be assuming/guessing, but I thought it was still possibly a hard thing to diagnose unless it was REALLY acting up?
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From: Allentown, PA
'08 GL 320 CDI
I did the work, myself. But I can still ask the question you posed. I suppose that's what I'm really wondering... Is it even possible to 100% diagnose the system via computers? For example, how would a computer know if a leak is in a bag, or the line going to the bag. It wouldn't, would it?
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From: Houston, TX
Mercedes Benz 2007 GL450 , 2012 BMW 528i
it might be normal for compressor to turn on once a while to keep the pressure up. If it is not running like crazy all the time, it is normal.
Did you change airstrut due to leaking airbag or bad strut ? Was compressor doing the same before or it is something new after the air strut change ?
if you change air strut due to leaking airbag and compressor is running less than before, it might be a normal operation.
If you changed it due to bad strut part, and compressor is running more after the change, you might have a leak. I don't have Star nor have used it, but I heard that it can point in the right direction but some diagnosis by yourself is required.
Did you change airstrut due to leaking airbag or bad strut ? Was compressor doing the same before or it is something new after the air strut change ?
if you change air strut due to leaking airbag and compressor is running less than before, it might be a normal operation.
If you changed it due to bad strut part, and compressor is running more after the change, you might have a leak. I don't have Star nor have used it, but I heard that it can point in the right direction but some diagnosis by yourself is required.
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From: Allentown, PA
'08 GL 320 CDI
I replaced the bag/strut because the bag was definitely leaking. Because of that, it probably wouldn't be fair to compare before to now. However, before I replaced the strut, I probably wasn't paying as much attention to it as now. That's why I'm wondering if I'm being overly sensitive... in other words, "looking for a problem where there really isn't". I'll stop by the dealer sometime and ask them if this is normal, or not.
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compressor operation is normal. the system tries to maintain specific height. however, said height is psi dependent and psi depends on a few things:
1. outdoor temp
2. system temp
3. vehicle load
those three variables will change during a normal day of operation so compressor will run on occasion. when you have the opportunity park the truck for a week and observe. no noticeable lowering should occur.
1. outdoor temp
2. system temp
3. vehicle load
those three variables will change during a normal day of operation so compressor will run on occasion. when you have the opportunity park the truck for a week and observe. no noticeable lowering should occur.
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From: Allentown, PA
'08 GL 320 CDI
Sounds like what's going on then might just be normal operation. Since I typically notice it on neighborhood roads that aren't exactly smooth, I suppose that could be playing into the mix and the compressor is trying to compensate?
Will do on letting it set for a week. Gotta go through the tank of fuel, fill it up, then I can switch to another car for a tankful on that car (an old '97 528).
Will do on letting it set for a week. Gotta go through the tank of fuel, fill it up, then I can switch to another car for a tankful on that car (an old '97 528).
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From: Allentown, PA
'08 GL 320 CDI
Sat for over a week and no change in height (confirmed by distance between tire and wheel arch). So it seems like it is normal for the pump to run for about 30 seconds every few minutes? But I don't want to make it sound like it is doing this all day long. I can only hear it at low, back-road speeds. Once I'm going a little faster, I think there is too much other noise to be able to hear. I also only spend a short amount of time on back roads.
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From: Allentown, PA
'08 GL 320 CDI
I certainly am a fan of preventative maintenance. But just because I'm curious, what's the thought behind doing this?
EDIT: Got knocked off wifi before I had a chance to finish.
Is it because the relay contacts (may be using the wrong term, there) start to get worn and possibly fail?
EDIT: Got knocked off wifi before I had a chance to finish.
Is it because the relay contacts (may be using the wrong term, there) start to get worn and possibly fail?
Last edited by DennisG01; Jun 5, 2017 at 11:24 AM.
