[fathobbit]

Hi,

I just bought a 2007 R500. May be the problem was there already when I bought but guess didn't notice it. Its just been just a week since I bought from a private party and I see that the car is tilted completely on the left side from the drivers perspective.

I took it to a mechanic the previous owner had been using and he said it could be due to a senor or some computer issue and that the left side it pushing in too much air.

He said he fixed it and told me try for a week. The second day the same problem occurred and I have dropped off the car again for checking.

Is this normal, fixable and wil not happen again. What would be price of repairs.

The car has bout 99500 miles on it.

Thanks

 

[rostrom]

When I had a leak in one air strut on my 2006 R350 the opposite side would get too high and over inflated. I think the system is trying to add air to the leaking side and over does it on the other? However, there should also be a sensor detecting if it is level, so maybe that went bad?

These air struts do tend to get leaks (I've replaced both of mine over the years). Don't let anyone tell you to replace the compressor or other parts unless they are 100% convinced it is not a leak in a strut.

 

[PeteinLongBeach]

It is likely a leaking air spring. Each corner is independently regulated by its own height sensor, so there is no "overcorrection" as suggested above.

Replacement air springs for reasonable prices (and installation instructions) can be found at https://www.arnottindustries.com/ .

If the bag is not actually leaking, then you have a calibration problem (perhaps due to previous work on the car). Recalibration can only be done with a STAR machine, usually at a dealer. But, check to see if the spring is leaking first. It sounds like your mechanic has insufficient experience diagnosing this system.

 

[starbound01]

A couple of points since your car is new to you (lessons from personal experience)...

Do not ignore air leak issues. They cascade and are very expensive to repair and will eventually cause the compressor to burn up if you ignore leaks - that's a $500-600 part depending on where you get it.

- You should consider the airmatic bags/strugs like shock absorbers on a regular car. The air bladder will eventually leak. Just like the struts/shock will eventually need replacement. Cost doesn't make it a design flaw, it's a wearable component.

- It is wise to replace the front struts and/or rear air springs in pairs. The MB OEM parts are crap because of the material the bladder is made from. You can find replacements from Arnott Industries. Many here (including me) have purchased them. The rears are very easy to replace and require simple tools and a little patience. The fronts require some mechanical skill. There is a good thread if you have the skills/tools. There are threads that talk about indy replacements for fairly low cost.

- Replace the airmatic relay!!!!! It's $20 from MB. It's a green relay in the main panel (3rd replay from the left as you look at it). I think the far left one is the starter relay. If the relay fails closed, as it did in my case, you will be replacing the compressor. I took apart the old relay and the contacts were toast.

- If you hear a loud WHOOSHH when you turn the car off, it's the exhaust hose from the compressor. It normally connects to a muffler in the fender well.. In my case it cracked at the compressor. Simple to fix and you can get the hose from any parts place. I cut off the cracked end and reattached it. I'm sure MB gets some rediculous price for it.

- You talked about the height being different. As the other poster mentioned, it can be calibration. However, IF one side/corner is high, you need to consider the valve distributuion block. It opens and closes each port independently to adjust the height. If you have the vehicle significanly high on one or more corners, you may have internal leaking in the block. It's quite common. The dealer replaced ours under warrantly. I think the part is a either $200 or $400. It looks fairly easy to replace but i don't know.

If you take the car to the dealer you can expect the following screw job.... they will tell you it's the valve block first, then the compressor and then the airbags. They get about $700 for the valve block another 1000-1200 for the compressor, 1800+ for each of the front struts and 1000+ for each of the rears. You can spend a lot of money at the dealer in a hurry. If you get the parts from somewhere like Arnott, and get an indy to do the work or do it yourself you can save a significant amount of money. There are good threads in here for how to do the work if you have the tools and skills.

last piece of advice.... if the car falls at a corner, its almost always the air bladder. You can read of lots of threads about how they couldn't find the leak, etc. The air leak is caused by road dirt and just the wear of rubber against metal. When your testing for the leak you have to keep in mind you have a 5K pound vehicle weighing down on the bladder and it almost always seals the leak until it's a big leak. If you want to attempt to find the leak, pull the 40A fuses for the airmatic in the fuse block and lift the vehicle where you extend the suspension. Then do soap bubbles (you'll have to take the wheel off). I've read where people have done that and it didn't show a leak. Don't forget to put the fuses back in.

 

[fathobbit]

Hi everyone,

Just got the car back and the mechanic said that it was not any sensor issue. He said all those look fine and things its a program issue, based on the thread replies I'm guessing he means calibration issue.

Apparently he had a friend in the dealership and took it there and tested/monitored the calibration and re-programmed.

Now will just have to see if that fixes the issue.

I think its just my bad luck/timing all this happened in less that week that I bought the car

I fact the other issue was also that the car keys being in the pocket and trying to open or lock the door from outside doesnt work all the time. I have only that in the pocket and nothing else. He changed the battery and said try it again and if not the key might be going bad.

Will Monitor the tilt and this and report back.

 

[fathobbit]

Back to square one in a couple of days. in fact now I think its tilting and sinking a little more on that one side towards the rear

Also this time, I'm noticing that my distronic has gone crazy, may be because its due to sinking but when I'm waiting for a light to do a U turn its beeping may be due to being next to the median in the street that it probably things I'm going to bump into it? We were actually just waiting in the parking lot or when driving for no reason (not cars close by) starts beeping.

 

[PeteinLongBeach]

Back to square one in a couple of days. in fact now I think its tilting and sinking a little more on that one side towards the rear

At the age and mileage on your car, the sinking is almost certainly a leaking air spring. And if it isn't now, it will be soon. I would go ahead and replace the pair. If that doesn't fix it, it's probably the valve block.

Think of the air springs like you would tires. They will eventually wear out.

 

[LuisAngel]

So if I hear a "Swoosh" like air leaking every time I stop and now my right hand front side is dropping every time I park my Benz, what exactly is wrong? the AirStrut? or the Compressor Hose?
P.S. ThanX a million for your Post! very informative!

 

[starbound01]

The Swoosh is very short and loud. Basically, the system is relieving the excess pressure from the system on the compressor side of the distribution block. If the hose breaks (as happened in my case) the air (at about 150psi) doesn't pass through the muffler and you will hear that as the Swoosh.

If you are hearing air hiss out of the front, it could be the valve distribution block or the air-spring.

You need to fix the issue soon as it will fry your compressor if you don't. You'll also get my standard advice to replace the compressor relay.

It also appears that the height sensors are becoming an issue. Likely because of age and exposure to the elements. You will read some threads about them being corroded and/or damaged.

If you open the hood and look behind the passenger side headlight you will see the distribution block with 5 translucent air lines plugged into it. With the system at a normal height, shut the car down and listen for the air you hear. If you hear it coming from the block, its the block leaking.

If you pull the right front wheel and do the same as above and hear the air-spring leaking - you know its the air spring. If they are original they are probably shot.

The front struts are much more effort to replace. I haven't done it myself, but it looks like a few hour job. I've read the anti-sway is the biggest pain point and it sounds like you have to uncouple both sides to make it easier. We are 55K on the replacement struts so I am expecting a replacement over the next year or so and I will do both and get it over with.

 

[bmccarther]

My 2008 R350 (W251 w/ rear airbags only) is still sagging rear right side. It started out intermittently being low, then back to normal, then low, then back to normal, etc. over a 6-week period. Then it got very low/near-flat (on the rear right side only) when the car was parked for an extended period of time. While driving or with the ignition in the on position, the rear right side would raise up to 2.5-3.5 inches, while the left rear side was up to 5+ inches in height.

Things I've done since the car when near-flat on the rear right side only:
- I've looked at the orange 40-amp fuse (which was not blown) located at the front right side (under the hood);
- I've replaced the $20 compressor relay (because I didn't want to test it) located in front of the 40-amp fuse;
- I've installed a new $170 Arnott airbag/air spring (which came with nearly fail-proof, instructions within the packaging...but be careful with the white, screw-on alignment plug...this is similar to a toggle for a toggle bolt but because it is made of plastic, the prongs can easily break after several failed attempts to hang the airbag in the proper alignment); and
- As of the morning of this message/reply, I replaced the $180 air valve which is located at the front right side (under the hood) in front of the right side wheel well (given only rear airbags, my valve has only 3 brass screws with a small color-coded, white, plastic lines: red and blue lines which go to each air bag in the rear and a brown line for the compressor/air tank line).

However, the car is still higher on the rear left (5+ inches) and lower on the rear right (3.5 inches). This must be sensor (either mechanical or electrical part) and/or it may require some calibration from some MB dealership tool/computer. Anyone have any options for me at this point or am I doomed to bring the car into the dealership?

 

[PeteinLongBeach]

It sounds like it has gone out of calibration. The dealer can put it on a STAR machine and re calibrate the heights. I would suggest you replace the other air spring first, as these parts should be considered "consumables" like tires, and it will fail like the other one relatively soon.

 

[bmccarther]

OK....this could be my problem: Rod_84 posted a photo on this thread: http://www.benzworld.org/forums/r230-sl-class/2116954-ride-height-2.html. It looks like the height sensor body is attached to the bottom of spare tire wheel well. The height sensor has an arm which is attached to some other bar/lever which is then attached to the rear underside of the control arm (behind the airbag). I don't know if the left sensor is overcompensating for a damaged/bent right sensor or bent/rusty/damaged right-side bar/lever.

I'll raise the car and compare both sensors and both bars/levers. Given the sensors do raise the car, I expect to see or measure that the sensor, the sensor's arm, or that the bar/lever is bent.

But this doesn't answer why the right rear goes completely flat overnight....unless I also have a small crack in the air line for the rear right side (color coded as red at the air valve block and the airbag).

 

[PeteinLongBeach]

It's still going flat on that side, even with the new air spring? Is it level when running? Your scenario isn't clear.
Unless you have reason to believe the height sensor was somehow damaged, this is not likely an issue.
If the car is still losing pressure and going flat, you might have a leak at the air line connection. Apply soapy water on the connection to check it.

No matter what, you still should replace the other spring and get the height calibrated at the dealer.

 

[bmccarther]

Thanks for your help Pete. Unfortunately, even with a new rear right air spring and a new air valve block, my R350 is not level under either of the following two scenarios:

(1) while the car is running, the left rear is 5+ inches above the tire and the rear right side is about 2.5-3.0 inches above the tire
(2) while the car has parked for an extended period of time (e.g. overnight), the left rear is 5+ inches above the tire and rear right is completely flat

Per your advice, I will look for air bubbles at both ends of the air line (at the air spring and at the air valve block). If the air line is the problem (and should be replaced), then I should consider purchasing part number 2513271645 (this is part number for the air line....it's about $14.00).

Also, you are correct, the air springs have a limited life....I need to replace the rear left side as well.

 

[bmccarther]

A week has gone by, and the rear right air bag/air spring holds pressure. This means that there are no air leaks from the air block valve, to the air lines, to the air spring itself. Research indicated that when the car is parked, it does lower itself a few inches.
Also, I raised my w251 (2008 R350) and I saw no visible problems with the sensors, the link/lever, or its connection to the control arm. Both left and right sides appeared to be properly positioned and all parts appeared to be in working order (see attached photos)

You can see the Arnott air spring I installed in one of the photos.

To PILB's point, I should replace the other air spring and take the car in for calibration. This video provided clarity as to what is involved with calibrating ride height using MB STAR software:

I don't the labor costs associated with calibration work...I'm guessing that this work shouldn't take a MB dealership more than 1.5 - 2.0 hours.

 

[oobc]

R500 Tilting on one side passenger rear.

Took it back to my mechanic who repaired, by replacing the air leak component months prior on the same side/area. He said there were no leaks. He said it could be rear stabilizer or something suspension related which I can't recall, but he said, it's expensive? Can't remember the part needed?

Was this R-500 suspension system ever a recall item? Because I see a lot of
R-500's with similar problems driven up and down the streets?

 

[bmccarther]

I feel like a fool (and I laughed at myself)…I finally fixed my suspension problem! My car is now measuring 18.5” on both sides (a height measured vertically from the center of the wheel up to the arc of the wheel well) and I didn’t take the car in for MB STAR sensor calibration!

Discovery, Cause, and Remediation:
I just replaced the rear left with the new air spring when the wife said that there was no harm in using my bottle of soapy water against the rear right air spring. I didn’t have a sprayer bottle of soapy water when I originally installed it. So, I sprayed the brass compression fitting, the air line, and the air connection at the air valve block. I started the car and let it run for 2 minutes. Yup…I got Bubbles! I failed to fully tighten the brass compression fitting against the rear right air spring! I removed the tire, grabbed a 10mm open wrench, and after a ½ turn, the bubbles stopped. That little air leak was holding enough pressure to fool me and keep the rear right side up for several hours.

So, lesson learned…..
The original rear right air spring very likely had a hair line crack. But I failed to properly install the new air spring because I thought I sensed resistance when initially tightening (I didn’t want to over tighten) the brass screw at installation. As a result, I spent about $400 more than I needed.

Final note:
I failed to properly determine air spring and airmatic differences between different MB models, chassis, and year of production. As such, I stand corrected in that my 2008 R350 on the W251 chassis is not programmed to lower itself when parked. My car was simply lower given all I’ve mentioned above.