Airmatic issue, need help
 

hey guys,


about 2 weeks ago I got a message that car will shut down some electrical components.
about same time I noticed that once I parked the car for few hours or over night the rear suspension goes very low.
as soon as I fire the engine I get a message say "stop, car too low".


after few sec the message is gone as the car goes back to its standard height.


few times the car remains in same height over night but most of the time it goes low in rear axle (front remain in normal height).


once engine fired all the suspension positions work properly (comfort, sport, lift etc').


I thought it might be related to that "electrical components" message and today I serviced my car and really needed to replace secondary battery and thought maybe the suspension issue is related but now I see car again got very low in the rear end.


any ideas?
how bad/expensive is it to fix?
any alternatives?
links?


thank you!

Rear air bags are leaking. Very expensive to fix with oem bags parts and labor. Much more inexpensive if you get Arnott bags and install yourself.

thank you for the reply!


whats the difference between the OEM bags to the one you recommended?


is it only new bags that need to buy or other parts as well? (if im correct the Arnott bags should cost about 800$ a pair, is that correct?).


for sure that's the cause of my suspension issue?


thanks again!

90% Reduction in Labor Using Arnott W211 Rear Air Springs
 

https://www.arnottindustries.com/par...34_gid963.html

The biggest difference will be in the removal of the OE springs and installation of the new air springs. The OE instructions involve lowering the entire rear end and exhaust just so you can remove and replace the OE reservoirs (About 6.5 hours). Arnott has designed its spring to not use the reservoir so you can simply leave the old one. According to one labor guide this will provide a 90% reduction in labor time when using the Arnott units.

Thank you for the info!

So to conclude, those arnott air bags should solve my current problems?

Does it "plug & play" or need any special fitting?

Do i need any to change any other parts? Control unit?

No it's plug and play. To get the old ones out you can also cut the tanks out instead of leaving them. Their video shows taking them out intact and it's way too much work.

Btw if you stay,in sport 2 they leak less. Takes days. In comfort or raised they leak faster. They will do this for years sometimes. Just depends on the leak.

Sport mode 2, great tip, i will keep the car in sport 2 at least till i put my hands on the arnott pair.

Many thanks!

By the way, is there any control unit which need to change?

you dont need to do anything as far as electronics are concerned. weird since my rear would drop overnight or maybe 2 days when in the lowered state on sport 2. now i park for about a week at a time in the raised and comfort mode and doesnt leak at all.

No kidding. Someone said theirs didn't drop in raised position and mine was slammed in 4 hrs. I guess it depends where the leak is. Airmatic is moody either way. Different everyday

As the weather gets colder, it'll get worse. I replaced all of mine with Arnotts ... they used to be decent pricing ... not sure about these days. They are slightly stiffer than stock. Really straightforward to install without having to mess with that additional reservoir.

Update,

Yesterday i was driving the car and all gone well.
Came back home and parked the car for about 3 hours.

Came back to take the car to go somewhere and i noticed left side of the car was in original level while the right side was all the way down (including the front right which never had any issues before).

I started the engine and the front right raised a little and than i heard a release pressure noise and it dropped back.
The rear right didnt raised at all, just stayed all the way down unlike other times which it was raised after few seconds.

Any ideas?

Again, never had issues with front suspension, it was only the rear that done issues in the recent 3 weeks and now all of the sudden left-back was ok but all the right side on the floor.

Thanks!

edan82, anything new with your car?

Mine started draining at the rear-left today, did it twice while parked, then once more for me while testing valve pressure values, and then hasn't dropped at all. I was trying to determine where specifically the leak was but couldn't pinpoint it since it stopped dropping.

Another strange thing was that I was next to the wheel, it was completely quiet, and then suddenly started hissing and dropping fast.

I'm not entirely new to this, I've done 6 front Arnott swaps already, but haven't had issues with the rears until now.

Sounds very interesting.. I can see how it makes sense. But, can you elaborate? Do you know this certain?

If you drive in sport 2 all the time the air springs will last longer less likely to leak? Or did you mean something else.

This is exactly how it went for me. Several months of my LR going low. First taking 3-4 days then down to overnight. Finally, one morning the whole left side was down and found out my LF bag went. It's an indication that the system is at the end of it's life. Two choices - as prior people said - do all 4 corners with Arnott, which is around $2300 in parts ($750 ea front, $400 ea rear) plus labor (figure about $800-$1000) or replace the whole system with coilovers. I went the coilover route and I am completely happy. The BC Racing coilovers for this car are made for street not track. The spring rate is not harsh at all and with damping/rebound around 3/4 towards full stiff they ride really nice. You can also adjust your ride height. The swap including parts and labor ( you also need to but non-airmatic rear control arms) was $2300 for me. $1050 for Coils, $850 labor, $250 control arms.

Is there any way to release the rear bag pressure on my E55 without Star so that I can install my Arnott's kit?

[QUOTE=erupert66;6633315] You can also adjust your ride height.

How do you adjust the ride height? My Arnott's kit struts have no thread on the body to adjust ride height and no mention of ride height adjustment in the instructions. Cheers.

[QUOTE=trabots;7733765]I think there's a misunderstanding; he was talking about the BC Racing coils when mentioning adjustable ride height. If you're wanting to lower your car with airmatic, there are plenty of threads on here that cover that topic. You can get a little bit of drop with STAR or some more with lowering links I think.

As for this, I believe you can disconnect the airmatic line that goes to the rear. Don't take my word for it though, hopefully someone more experienced can chime in.

[QUOTE=N_Rob;7733768]Cheers, the Arnott's instructions clearly warn of the danger with these bags carrying 150 bar of pressure. They say that only the Star can signal the solenoid valve to release the pressure. I have to pay $180 for that at the Merc dealer and then hope I can drive home with the bum on the ground. I was hoping someone had worked out what electrical signal to send directly to a bag. While I am there I will ask if they can totally disable the Airmatic while on Star. Possibly not because Arnott's has included a piggy back to attach to the Airmatic ECU which disables it and removes error messages.

Two solenoids in the rear air spring. They share a common lead and each have their own ground (assuming a pull-down circuit). Apply 12 volts across the connector pins. Three pins between the two solenoids; you may need to reverse polarity if the solenoid doesn't open on the first attempt. I would assume (but do not know for sure) the center pin is the common pin and the two outer pins are for each of the solenoids. Loosen the air line at the T-connector located in the center of the subframe (follow the air lines to it) to allow the air to bleed to atmosphere.

If removing the original factory air springs, cut the large rubber hoses between the old air springs and the aluminum reservoirs (after you get the air springs deflated). You can then unbolt and pull the reservoirs out from under the car. When reinflating the new air springs, there is a step-by-step process required to prevent damage to the new air springs. A description is in my post here: https://mbworld.org/forums/w211-amg/...ml#post7404390

STAR makes it so much easier to perform the process above.

So I went to put the car on my hoist to de-pressure the rear bags after having just driven it an hour earlier. No start, lots of noises but no classic solenoid noise of it trying to engage the flywheel. Checking the battery showed 13 volts, even after many times letting a trickle charger bring the battery up to 16 volts, no indication of the starter being asked to work. With the Airmatic disabled by pulling 2 fuses and my ignoring "drive to shop" and error messages etc for 2 days after replacing the fronts only with coil overs, will the ECU finally refuse to allow a start?

I’ve installed rear airbags last November, cut the stock hoses and bags can be remove with minimal difficulties. I didn’t need to deflate them prior but we’re very conscious not to get my hands caught between anything that could collapse when hoses were cut. YouTube got a few “how to” that help my research to complete DIY. Scale of difficulty is a 5.9 out of 10 and it was my first time doing it. Also Arnott got two video version on DIY, I didn’t follow the one that removes the whole rear end. Took me about an hour each side. Pm me if your stuck.

Thanks for that but I need to get the car started first. I was wondering if there are situations where the ECU will finally refuse an engine start if there are unattended issues it regards as safety concerns.

idk, never had that problem ever where it won’t start. Wouldn’t make any sense for ECU to shut down cause it makes things difficult to diagnose problems for fixes.