My car can sit for days with no suspension sag anywhere?
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GLS450
My car can sit for days with no suspension sag anywhere?
Since I get no suspension sag after the car sits for several days how could I have an air bag leak???
I’ve checked all of the pump and valve block fittings with soapy water…no leaks.
My Malfunction error MUST be due to some other issue, right?
Faulty valve block?
leak in central reservoir?
P-3722 pump is only a few days old
I’ve checked all of the pump and valve block fittings with soapy water…no leaks.
My Malfunction error MUST be due to some other issue, right?
Faulty valve block?
leak in central reservoir?
P-3722 pump is only a few days old
Out Of Control!!
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From: unbegrenzt
2017 GLE350 4MATIC
Since I get no suspension sag after the car sits for several days how could I have an air bag leak???
I’ve checked all of the pump and valve block fittings with soapy water…no leaks.
My Malfunction error MUST be due to some other issue, right?
Faulty valve block?
leak in central reservoir?
P-3722 pump is only a few days old
I’ve checked all of the pump and valve block fittings with soapy water…no leaks.
My Malfunction error MUST be due to some other issue, right?
Faulty valve block?
leak in central reservoir?
P-3722 pump is only a few days old
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From: Allentown, PA
'08 GL 320 CDI
It could be something else - but sitting like you're saying doesn't guarantee that there's no leaks in the bags. It could be in the fold. Raise the vehicle and try again.
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GLS450
Luv the way you know my next step!!!LOL
icarsoft MB ll is, for my level of brain power, only slightly helpful.
What really fractured my mind last evening as I was getting ready to install the new Arnott (European) valve block is I found that the airline coming out of the newly installed compressor had blown out, i.e. it wasn’t even connected and I don’t know for how long.
An Arnott technician just emailed me instructions on how to rectify this. On and on!!!
What really fractured my mind last evening as I was getting ready to install the new Arnott (European) valve block is I found that the airline coming out of the newly installed compressor had blown out, i.e. it wasn’t even connected and I don’t know for how long.
An Arnott technician just emailed me instructions on how to rectify this. On and on!!!
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From: Emmett, ID, USA
2007 GL450
There is nothing wrong with your MBII. It is a fine tool, and the only shortcomings are that it is not bidirectional, and is usable only on MB. The latter may be a benefit for those who wish to have the simplest tool possible.
Tools such as the Autel MP808 interface with (supposedly) all modules on (supposedly) all makes and models.
But, yes, your Airmatic error is almost certainly "taking too long to refill reservoir", which your MBII was itching to tell you.
In case this is not clear to anyone else: There are two levels of trouble codes. One is the generic, usually prefixed by a P for Powertrain. These are the codes that trigger a Check Engine light. When you get a simple OBD reader, like a bluetooth dongle and Torque on your phone, and you ask it to check for Fault Codes, this is what it will report.
The deeper level is manufacturer-specific and module-specific diagnostic trouble codes. All codes start life as this level, and if they are considered serious, they are elevated to the Check Engine light system.
Airmatic codes will usually trigger a Malfunction message on the central display, but they will not trigger a Check Engine light.
You have to use a tool, that knows what the Airmatic system is, to go into the Airmatic system and ask it what is going on. In this case it would reply "Help, I'm running the compressor but the pressure in the reservoir is not rising."
Tools such as the Autel MP808 interface with (supposedly) all modules on (supposedly) all makes and models.
But, yes, your Airmatic error is almost certainly "taking too long to refill reservoir", which your MBII was itching to tell you.
In case this is not clear to anyone else: There are two levels of trouble codes. One is the generic, usually prefixed by a P for Powertrain. These are the codes that trigger a Check Engine light. When you get a simple OBD reader, like a bluetooth dongle and Torque on your phone, and you ask it to check for Fault Codes, this is what it will report.
The deeper level is manufacturer-specific and module-specific diagnostic trouble codes. All codes start life as this level, and if they are considered serious, they are elevated to the Check Engine light system.
Airmatic codes will usually trigger a Malfunction message on the central display, but they will not trigger a Check Engine light.
You have to use a tool, that knows what the Airmatic system is, to go into the Airmatic system and ask it what is going on. In this case it would reply "Help, I'm running the compressor but the pressure in the reservoir is not rising."
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GLS450
Sat for 3 hours at fully raised height, no sag
So, I tackled R&R of new valve block. As most of you speculated there was no hole burned through the base BUT I’m thinking the one I’m replacing must be the elcheapo Chinese version as it has no numbers or letters anywhere on it, i.e. absolutely nothing to identify it. The Chinese Arnott block and the European ones I bought from Rockauto both have lots of identifying info on them. I’ll be sending the Chinese unit back for a refund.
Of note, a P-3722 costs a little over $360 from Rockauto and $750 from my local NAPA dealer!
I hope to button this project up this weekend and I’m praying my problem was caused by the noname valve block.
Of note, a P-3722 costs a little over $360 from Rockauto and $750 from my local NAPA dealer!
I hope to button this project up this weekend and I’m praying my problem was caused by the noname valve block.
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From: Melbourne, Australia
2010 ML550 VIN WDC1641722A564750, 2010 B180
Hopefully the valve block is your fix. My experience with the air bags is that not only can they hide in the folds as others have said, but small leaks can only be located with the soapy water test if the bags are fully inflated AND resting on the weight of the car. I needed the additional pressure caused by the car's weight to find mine. Best of luck
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From: Emmett, ID, USA
2007 GL450
Hopefully the valve block is your fix. My experience with the air bags is that not only can they hide in the folds as others have said, but small leaks can only be located with the soapy water test if the bags are fully inflated AND resting on the weight of the car. I needed the additional pressure caused by the car's weight to find mine. Best of luck
To check for ordinary, age-related leaks: Press the suspension lift button on the dash. Wait for the suspension lifting procedure to complete.
Place jack stands under the end you wish to inspect, at a height close to but not touching the frame.
Spray soapy water on the air springs, paying particular attention to an area about three inches above the fold. Look for air bubbles, particularly fine foam, which indicates an early leak.
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GLS450
99% certain
I’m 99% certain my entire problem was the NONAME valve block that a previous owner probably bought on Amazon for under $100.
All seems to be working well now!
Thank you to all who helped me on this journey!!
All seems to be working well now!
Thank you to all who helped me on this journey!!
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Mercedes gl450
You're going to return a no-name Chinese valve block that the previous owner installed?
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GLS450
No
I hardly feel that would be appropriate after it has been in my car for the four years I have owned it and I didn’t even buy it in the first place.
I bought an Arnott valve block from Rockauto about a week ago when I started this project and they sent me the Chinese Arnott unit (3267, I think). I didn’t even know Arnott offered two valve blocks until I talked to one of their technical guys and he recommended I not use a 3276 and that I should use their European made 3823 unit. Why in the heck they sell a Chinese block that they don’t even recommend I’ll never know. Both blocks are about the same price, too!
At any rate there are AT LEAST three valve blocks available for a GL450, i.e. the noname one you buy on Amazon for well under $100 like was on my car when I bought it that caused my problems, the Chinese Arnott one even they tell you not to use for about $250 and the European Arnott unit for about $250.
So, I’m returning the unused Chinese Arnott unit to Rockauto. Sorry to be so wordy!
I bought an Arnott valve block from Rockauto about a week ago when I started this project and they sent me the Chinese Arnott unit (3267, I think). I didn’t even know Arnott offered two valve blocks until I talked to one of their technical guys and he recommended I not use a 3276 and that I should use their European made 3823 unit. Why in the heck they sell a Chinese block that they don’t even recommend I’ll never know. Both blocks are about the same price, too!
At any rate there are AT LEAST three valve blocks available for a GL450, i.e. the noname one you buy on Amazon for well under $100 like was on my car when I bought it that caused my problems, the Chinese Arnott one even they tell you not to use for about $250 and the European Arnott unit for about $250.
So, I’m returning the unused Chinese Arnott unit to Rockauto. Sorry to be so wordy!
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Mercedes gl450
I hardly feel that would be appropriate after it has been in my car for the four years I have owned it and I didn’t even buy it in the first place.
I bought an Arnott valve block from Rockauto about a week ago when I started this project and they sent me the Chinese Arnott unit (3267, I think). I didn’t even know Arnott offered two valve blocks until I talked to one of their technical guys and he recommended I not use a 3276 and that I should use their European made 3823 unit. Why in the heck they sell a Chinese block that they don’t even recommend I’ll never know. Both blocks are about the same price, too!
At any rate there are AT LEAST three valve blocks available for a GL450, i.e. the noname one you buy on Amazon for well under $100 like was on my car when I bought it that caused my problems, the Chinese Arnott one even they tell you not to use for about $250 and the European Arnott unit for about $250.
So, I’m returning the unused Chinese Arnott unit to Rockauto. Sorry to be so wordy!
I bought an Arnott valve block from Rockauto about a week ago when I started this project and they sent me the Chinese Arnott unit (3267, I think). I didn’t even know Arnott offered two valve blocks until I talked to one of their technical guys and he recommended I not use a 3276 and that I should use their European made 3823 unit. Why in the heck they sell a Chinese block that they don’t even recommend I’ll never know. Both blocks are about the same price, too!
At any rate there are AT LEAST three valve blocks available for a GL450, i.e. the noname one you buy on Amazon for well under $100 like was on my car when I bought it that caused my problems, the Chinese Arnott one even they tell you not to use for about $250 and the European Arnott unit for about $250.
So, I’m returning the unused Chinese Arnott unit to Rockauto. Sorry to be so wordy!
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From: Emmett, ID, USA
2007 GL450
MBWorld Fanatic!
Joined: Jun 2010
Posts: 2,755
Likes: 628
From: Emmett, ID, USA
2007 GL450
I hardly feel that would be appropriate after it has been in my car for the four years I have owned it and I didn’t even buy it in the first place.
I bought an Arnott valve block from Rockauto about a week ago when I started this project and they sent me the Chinese Arnott unit (3267, I think). I didn’t even know Arnott offered two valve blocks until I talked to one of their technical guys and he recommended I not use a 3276 and that I should use their European made 3823 unit. Why in the heck they sell a Chinese block that they don’t even recommend I’ll never know. Both blocks are about the same price, too!
At any rate there are AT LEAST three valve blocks available for a GL450, i.e. the noname one you buy on Amazon for well under $100 like was on my car when I bought it that caused my problems, the Chinese Arnott one even they tell you not to use for about $250 and the European Arnott unit for about $250.
So, I’m returning the unused Chinese Arnott unit to Rockauto. Sorry to be so wordy!
I bought an Arnott valve block from Rockauto about a week ago when I started this project and they sent me the Chinese Arnott unit (3267, I think). I didn’t even know Arnott offered two valve blocks until I talked to one of their technical guys and he recommended I not use a 3276 and that I should use their European made 3823 unit. Why in the heck they sell a Chinese block that they don’t even recommend I’ll never know. Both blocks are about the same price, too!
At any rate there are AT LEAST three valve blocks available for a GL450, i.e. the noname one you buy on Amazon for well under $100 like was on my car when I bought it that caused my problems, the Chinese Arnott one even they tell you not to use for about $250 and the European Arnott unit for about $250.
So, I’m returning the unused Chinese Arnott unit to Rockauto. Sorry to be so wordy!
By the way, if I recall correctly, you swapped the pump and then then noticed the pump supply line was not connected. Then you swapped the valve block (if I understand the above correctly). Did you test the system after reconnecting the supply line?
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From: Emmett, ID, USA
2007 GL450
Now, to be fair, Arnott Chinesium is likely better than Amazon Chinesium, so your statement about what we insist is not incorrect. But if anyone does towing, we are clear that one should put Bilsteins in the back. Fronts, I'd probably go with Bilsteins also. AMK pumps. No one replaces the valve block, so that's almost a moot point.
Last edited by eric_in_sd; Feb 5, 2024 at 02:47 PM.
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GLS450
Valve block
My testing was by intuition, a common mistake I make but hopefully not this time.
I decided the valve block was the problem and when I removed the block in my car and compared it to the two blocks I had just received from Arnott, both of which were well labeled and marked, I noticed that there were no identifying numbers, letters or anything else on the one I had removed from my car and that I suspected was faulty.
I’m assuming it is an Amazon, under $100, junk block.
I installed the European Arnott 3823 and will be returning the unused Arnott 3267 to Rockauto.
So far my car is performing well and I get no MALFUNCTION message. 🙏
I decided the valve block was the problem and when I removed the block in my car and compared it to the two blocks I had just received from Arnott, both of which were well labeled and marked, I noticed that there were no identifying numbers, letters or anything else on the one I had removed from my car and that I suspected was faulty.
I’m assuming it is an Amazon, under $100, junk block.
I installed the European Arnott 3823 and will be returning the unused Arnott 3267 to Rockauto.
So far my car is performing well and I get no MALFUNCTION message. 🙏
MBWorld Fanatic!
Joined: Jun 2010
Posts: 2,755
Likes: 628
From: Emmett, ID, USA
2007 GL450
My testing was by intuition, a common mistake I make but hopefully not this time.
I decided the valve block was the problem and when I removed the block in my car and compared it to the two blocks I had just received from Arnott, both of which were well labeled and marked, I noticed that there were no identifying numbers, letters or anything else on the one I had removed from my car and that I suspected was faulty.
I’m assuming it is an Amazon, under $100, junk block.
I installed the European Arnott 3823 and will be returning the unused Arnott 3267 to Rockauto.
So far my car is performing well and I get no MALFUNCTION message. 🙏
I decided the valve block was the problem and when I removed the block in my car and compared it to the two blocks I had just received from Arnott, both of which were well labeled and marked, I noticed that there were no identifying numbers, letters or anything else on the one I had removed from my car and that I suspected was faulty.
I’m assuming it is an Amazon, under $100, junk block.
I installed the European Arnott 3823 and will be returning the unused Arnott 3267 to Rockauto.
So far my car is performing well and I get no MALFUNCTION message. 🙏
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From: Allentown, PA
'08 GL 320 CDI
Do a quick test - if for nothing else than to further justify that you're all good. In your driveway, raise the vehicle and leave it that way overnight. If all is good: (1) You won't get a malfunction message during the raising and (2) It will still be raised to the same point come morning (for good measure, measure the distance between each tire and fender to compare in the morning).
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GLS450
Raised to maximum height
No sagging overnight and no malfunction error displayed.
But concerning is that I still get the occasional strong burning plastic smell.
Also, to get the car to raise I have to hit the Airmatic button AND the button next to it ( uneven road?). I don’t think I had to do that before all of this!
But concerning is that I still get the occasional strong burning plastic smell.
Also, to get the car to raise I have to hit the Airmatic button AND the button next to it ( uneven road?). I don’t think I had to do that before all of this!
MBWorld Fanatic!
Joined: Jun 2010
Posts: 2,755
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From: Emmett, ID, USA
2007 GL450
No sagging overnight and no malfunction error displayed.
But concerning is that I still get the occasional strong burning plastic smell.
Also, to get the car to raise I have to hit the Airmatic button AND the button next to it ( uneven road?). I don’t think I had to do that before all of this!
But concerning is that I still get the occasional strong burning plastic smell.
Also, to get the car to raise I have to hit the Airmatic button AND the button next to it ( uneven road?). I don’t think I had to do that before all of this!
