Airmatic repair questionsI've only owned my E550 for about a month and since I purchased it private party I figured it was good to have a proper diagnostic done of the car by the dealer. Of particular concern to me was the suspension because in the mornings my car has been sitting low and has to go through the vehicle rising lately every day. Aside from that, the ride quality is also questionable even though I bought new tires and had an alignment done. The car makes a clunking sound at slow speed in the morning driving over small bumps in the road. Coming from non airmatic cars it sounds to me like a sway bar bushing or some other bushing.

After checking it over, the dealer told me their mechanics determined the car to have a bad valve block. Since they would apply the cost of the diagnostic to the repair and I'm busy with work at the moment I figured it was worth having them replace it. But, after replacing the part, they told me the car is lowering in the rear after it sat for an hour. And that's when I regretted having them replace the valve block because I know these repairs can snowball once it's in the dealers hands. As it is, when they did the initial diagnostic I told them to proceed having trust that they have the diagnostic equipment to pinpoint the problem and not just throw parts at it like myself or an independent.

At the time, the car is still being diagnosed to find out what is the problem, but I am curious about a few things that I hope you guys can answer. Could I have replaced the valve block myself? Is it a matter of just removing and replacing the part?

I bought the Mercedes service manual download and I own the iCarsoft Mercedes code reader but I can't tell if the airmatic system is a something I can service myself. If the dealer tells me the front or rear air struts are leaking I'm taking my car back and I'll replace them myself. Thoughts or recommendations?

 

Hi there Paul,

I just went through something similar and outlined my process in the other thread you replied to. The valve block is a very straight forward job with only basic tools required. I did min in 0 degree weather without issue. If you search on here you will find lots of useful tips. I replaced the compressor as well. Again not complicated but, the use of a friends heated garage and a lift made the job very easy. The last thing I replace and what actually fixed the problem was the rear airbags. The easies of the three jobs. Just search the forum for the DIY on that. I drilled a hole in the hard plastic part, let the air out, compressed the bag and hit the bottom up with a hammer, installed the new bag and good to go. I have noticed that my suspension is smoother overall, with a new valve block, compressor and rear air bags. In the process of these repairs I did notice the left rear shock has been leaking. I replaced these at about 60K and now I'm at 123K I wish they either lasted longer or were way cheaper!! Another easy straight forward job though. And I am noticing a clunk/ type of sound at slow speeds over bumps. This is what happened at the 60K mark as well.

Other than the original diagnostic at the dealer, I did everything myself, no re-programming needed.

Good luck!
Brad

 

Tell the dealer to remove the valve block and install your old one and give you your money back or work with you on the cost to provide a proper solution. I would be very pissed. Airmatic systems are not as complicated as you think, but they do require careful diagnosis when acting up.

 

Do the valve blocks give an error code when they go bad because I'm trying to figure out if the dealer is just guessing as well I don't mind paying for it if the part is actually sad but that's what really prompted my original question. Also is there a second battery in this car that drives the air Maddock system or is it all coming off one main battery And lastly when it comes to the valve block the compressor the lines and the air struts are these parts that can be removed and replaced without having to do any sort of re-setting of electronics?

 

Read this thread in its entirety may be wiring: https://mbworld.org/forums/e-class-w...ompressor.html

 

I would DITTO the suggestion if it would be realistic in real life.
The deal is that it was the owner who agree on valve replacement and that is how it plays with shops.
Still remember days when digital cars come on the market (we bought 1998 ML at the time).
Lot of times fellow members report that having intermittent problem they agree to dealer's suggestion to replace $2500 computer module. After some driving the problem still exist, so dealer suggested replacing other $1500 module, that again did not solve intermittent problem.
So on 3rd visit dealer troubleshoot bad $150 sensor, what finally solved the problem, but still leaving the owner short of 4 grands.

 

I read it that does not describe what my car is doing my car has a tendency to sag after it’s been sitting especially if it’s very cold outside What I’m starting to suspect is that if the rear airbags are losing pressure through a slow leak then the car self levels itself lower and lower Up till now I’ve been assuming it was the front airbags but those seem like they are not replaced very often. Am I correct about that?

 

Even I no longer own airmatic, I follow those topics as pneumatic drives were 1 of my majors at school
So trying to answer the question - the system is too complicated to make simple assumption.
Car coming down can be result of:
1, airbag leak (rubber has natural molecules migration, so it is natural when car sags after few days)
2. airbag valve leak combined with:
-check valve leak or
-compressor manifold leak or
- air line leak.
Monitoring pressure in the line will answer some questions, but MB did not design system available for drivers.
Meaning without scanner you can rub the crystal ball all you want and still not get it right.
When I had a leak, cheap scanners were not available, so I add pressure gauge to the system. Easy, cheap and very convenient. The same fitting allow me hooking up garage compressor for tracing pinhole in the system.
Now $150 scanners will troubleshoot the system, but I don't know if they will allow you to activate the compressor. I know MaxiEcu has the programs, but now I have no way to use it.

 

I textd my service advisor at MB to put my old part in the car and I will pick up tomorrow. I anticipate they will resist doing it but since they gave me push back when I asked for my old part back already and questioned what my intentions were I’m already convinced it’s either not bad or if it is I can swap it for a new one from FCP myself. I’m in this predicament because I read other threads repeatedly saying that star was necessary to pinpoint problems.

 

Even Star can’t necessarily tell you that the leak is in a line. Once again, it takes diligence to sort many Airmatic issues. My guess is one or both of the rear air springs is failing, based totally on what is usually being replaced around here.

 

Can star tell you if the valve block is bad or is that just a guess on the part of the service department? The car has over 70,000 miles on it so I wouldn’t hesitate to replace the rear air struts myself. it doesn’t sound like a very hard project compared with replacing all the control arms on my W210 E320 that I did earlier this year.

For those who have replaced the rear struts on your car when they go out does the car sag just in the rear or does the car self level itself all the way down?

 

Any scanner can only tell you what it can sense.
In case of bad sensor, or electrical short - this is an easy task. But there are no sensors on air tubings, who would determinate a leak.
You see end result what is low car, but computer doesn't have a program to give you a warning.
The only thing the car computer sense is compressor run overtime and that is when dash symbols show.
So at the finish line - it takes technician intelligence to observe pressure build and pressure drop to start narrowing possibilities. As I post above, it can be quite a maze.

 

Check your PM.

 

This is all making king a lot of sense to me now. I emailed the head of the service department explaining my situation hopefully they won’t give me a bunch of stuff about putting my old valve block back in. I cannot believe that a valve block intermittently goes out it’s going to either be good or bad and if it’s bad using my logic the Karwood constantly have problems keeping inflated this morn more sounds to me like an airbag situation especially in the rear. My wife told me that when she turned the car off she hears spittle and hit it’s not a long his *** but it’s like tapping on a tire hose at the gas station. I haven’t heard that sound myself but that’s what she describes According to her it makes a couple quick hissing sound and that’s it and it sounds like it’s inside the trunk somewhere near the back of the car But maybe that’s the relief valve doing it’s job correctly?

 

Hissing, poping, farting are all normal for a properly operating Airmatic system. Don’t be fooled by that. These are very busy and noisy cars.

 

First step pull codes, no codes check entire system for leaks, no leaks check harness to compressor as depicted in thread suggested previously. Although attached bulletin 048597 applies to rear (should also be checked for precaution) same remedy principles apply to front i.e.: leak, moisture, etc. As you can see by attachment front strut was replaced multiple times, and rear once normally indicating modification. Bulletin 052062 addresses front thumping sound.

Doubt you have a solid argument to replace front struts if leak is found at strut however, you can argue for MBUSA 800-367-6372 (not dealer) goodwill free repair and/or assistance for compressor & valve replacement if moisture is found together with rear spring replacement (defective part installed @ production) and thumping (control unit software error @ production) both applicable to your vehicle.

 

I called Arnott and asked their opinion. They agree that if the valve block were the problem the car would be fixed and the fact that the dealer assumed it was the valve block they agree that putting my original part back in and picking up the car is the right option

I’ve already asked for my car back and I’m anticipating some arm wrestling with them trying to charge me labor for work that was BS. I can get the car back I’m gonna pull the rear wheels off and spray down the airbags with soapy water to check for leaks. And this is what I assume the dealer was going to do or use a pressure leak test I bet my belief is that they walked up to the car after seeing Park for a day they saw that it was dropped on all four sides and they started throwing parts at it.

 

It's a shame you didn't spend more time here asking questions and reading up on Airmatic issues prior to dropping it off at the dealer. I know that is moot now. How many miles are on your car? I looked through the thread and did not see the mileage listed. I have had an '04 E500 and an 2010 E550, both with Airmatic and understand the issues they bring. I was fortunate enough to avoid most headaches with the system and actually still prefer the Airmatic ride over springs. My current E550 is a spring suspension and it is not a perfect ride.

 

The car has 77,000 miles and the good news is because I spoke to the general service manager and explain the situation he’s putting my valve block back on and not charging me any of the labor just the inspection fee that I had earlier agreed to.

The reality is they replaced the valve block and it didn’t fix the car and they can’t find any other leaks but they did admit that the rear shocks have a cover over them so they can’t tell if there’s a slow leak coming from those struts so most likely they need to be replaced.

 

That is great news and I commend you for standing up for a proper fix. I had to replace one rear strut (not air spring) on my E500 as it was causing the car to drop. It also blew my compressor as a result and I had to replace that as well. I'm sure you will get it sorted and it very well could be leaking strut(s).

 

They should. I did not have big scanner to play with it, but to my knowledge, the system has pressure sensor behind compressor and then level sensors and probably pressure sensors at each bag.
You can monitor pressures/levels and tell when it leaks. As I said above >>> takes technician with some intelligence.

 

Ordered the Arnott rear airstruts and the quicklift 5000 today. For what the dealer would have charged for the airbags I’m still ahead I figure.

 

Got my Arnott airbag set. Seems like this is going to be easy. Soooe with Arnott and apparently on this car the rear end doesn’t need to be disassembled to replace the air struts.

The pair of air struts was under $400 and doing it myself justified buying a quick lift. I’ll shoot video if the process

 

Does anyone have access to the maximum vehicle level mismatch ? I am have a consistent 5 mm difference in the back. Scanner reports NO error codes.

 

Glad to hear that as my wagon has been making those noises.