hujirong

Symptoms as below, what do you suggest?

1. The front air suspension is down. The passenger side is 1/2cm lower than the driver side. The whole car is tilted to the passenger side.
2. The air pump starts to run once the car is unlocked, but stops when the front suspension is only half way up. I can hear the air pump.
3. Starts the car, the front suspension will be all the way up, and drive normally.
4. Within an hour, the front suspension will be back to down again.
5. No message on dash.
6. No error code found, no live data provided by the iCarSoft MB II scanner.
7. Visually check the front suspension, air bags, while car on ground and wheels still on, using soapy water, can’t find obvious leak.

Driver Side:
https://cdn.discordapp.com/attachmen...229_112407.jpg
Passenger Side:
https://cdn.discordapp.com/attachmen...140133.jpg2013

R350 BlueTec 4Matic, VIN: 4JGCB2FE8DA161701, W251, Diesel, 100kkm.

hujirong

Best post found so far: https://mbworld.org/forums/mercedes-...ic-issues.html
Original article: https://www.mercedesmedic.com/air-su...isit-workshop/

Most likely the passenger side air strut has leaks? Tomorrow let me remove the strut tower cover and also check valve block and air lines.

hujirong

Found the issue, the air line cracked. The small one is very obvious, the large one not that much.
Now how to fix this:
1. Cut the bad lines, but how to make the end a bit round like that? See the last photo.
2. Found two lines leaking, passenger side front and rear, matches to the symptoms. Shall I do all 6 lines?
3. To replace the whole lines with new seems too much work.

wallyp

I would look for new end fittings, and just cut off the split area and re-attach.

hujirong

Not sure where to find these end fittings. I cut the end of these two leaking lines, put it back this morning, so far so good, but the rear right (the most cracked smaller line) is still lower than rear left. Initially the problem was front right down most, rear was all normal.

I am going to leave it like this for a few hours more, then drive it to see if all sides will be leveled. Then leave it overnight, a few days, see how it goes.

chassis

The fittings look like standard tube/compression fittings. Likely metric, which could be hard to find or order, other than from an MB parts source (dealer, etc.).