replaced front struts, valve body, and compressor still leaks
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2012 Mercedes Benz S550 W221 M278 4.6 twin turbo
replaced front struts, valve body, and compressor still leaks
The left front strut blew out on my 2012 S550 W221 M278 4.6 lt twin turbo 110,00 miles, showering the wheel well with rusty water. Thinking it would be a good idea to repalce the entire front end air suspension parts I did that (both air stuts, the valve body control, and the air compressor). I also replaced the electrical relay, 40 amp fuse and both fuses to the compressor. The system was charged and rose, however, as soon as the compressor stopped both sides in the front dropped too low to drive, however, the back remained in the drive mode (right height) I checked for leaks using the peferred method (spraying w/ leak detector.) No leaks I can find. The drivers side control arm was alo replaced when I stripped the bolt holding the arm to the suspension. I put everything back the way it was and secured both control arms with new nuts and torqued them to specs. and then installed the strut. I kept everything the way the manuel said when putting the new parts on. Any ideas on what is making the stuts fall?
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S500
what is the condition of the level sensors ?
if all the bits are genuine / or reputable fault free after-market parts there isn't much to the system
its either broken bits, wrongly fitted bits or something is telling it to behave incorrectly - its nothing more sophisticated than your finger over the end of a bicycle pump
if all the bits are genuine / or reputable fault free after-market parts there isn't much to the system
its either broken bits, wrongly fitted bits or something is telling it to behave incorrectly - its nothing more sophisticated than your finger over the end of a bicycle pump
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2012 Mercedes Benz S550 W221 M278 4.6 twin turbo
Air suspension
Well I know that there are load sensors/levelers attached to the frame next to the upper control arm. I don't know what you mean by "bits". I assume that their positioning is how the car stays level. Other than that no clue. I did read were you need a special tool to calibrate the sensors. None of the DIY readings even mention those in the replacement/installation of any of the air suspension parts I read. Everything went in fine in the installation process other than damaging the bolt treads when I removed upper control arm from the suspension. I replaced that so I had to remove the level sensor from the frame since it was held in place by the upper control arm bolt. If that was the probrlm then I don't understand why the passenger side would not rise when charged since the upper control arm on that side was not removed. I am sure this problem is an easy fix, yet, I don't know how to proceed at this point.
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S500
how fast does it drop to the floor ?
the level sensors are critical - the link rods seize so the car sits out of wack leaving the car confused as to the height the car is really sitting at, and then snap off beaching the car - they are the FIRST service item prior to doing any activity on the suspension - there are three one each on the top of the front struts and one more near the diff at the back
fitting new parts should not change the level the car sits at (unless its desperately in need of basic maintenance) - if it tries to get to height but randomly drops a bit check level sensors and or small air leaks
the level sensors are critical - the link rods seize so the car sits out of wack leaving the car confused as to the height the car is really sitting at, and then snap off beaching the car - they are the FIRST service item prior to doing any activity on the suspension - there are three one each on the top of the front struts and one more near the diff at the back
fitting new parts should not change the level the car sits at (unless its desperately in need of basic maintenance) - if it tries to get to height but randomly drops a bit check level sensors and or small air leaks
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2012 Mercedes Benz S550 W221 M278 4.6 twin turbo
S550 too low
I thought about the control arm that I had to remove when I damaged the bolt on the drivers side. I did not notice it's position when I took it off the car (it seemed that it moved easily). When I replaced the other strut I noted that the upper control arm was almost stiff. I took the left front wheel off today and noted that sensor lever was pointed straight down. Seems to me it should level. So I moved the whole wheel assembly up to where the control arm was almost level and tightened the nuts holding the control arm to specs. I apparently left the control arm initally too loose causing it to push the sensor lever too far down. When I lowered the car back onto all the wheels it was still too low (about 1/2 inch), however, it's not close to the ground it was and is now driveable, I think. I ordered a pair of level sensors and will install the day I get them. I'll advise of the results.
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From: Republic of Texas
W203 W212 W211 R53MCS
You gotta have a leak for sure. As soon as you turn the key off all power is removed from Airmatic module and all valves should remain closed. Check the lines on top. Maybe those are leaking.
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S500
the level sensor link rods fit to these steel *****, by two plastic socket joints which should allow smooth rotation. The link rod has a bit of flex at the point the lower ball fits on the suspension arm. This flex comes from 4 tiny link arms (each 2mm in width) which is part of the sprung steel bracket holding the steel ball to the car's suspension arm. Once the plastic socket joints seize to the steel *****, these four link arms deform and start to crack one at a time. When the last leg snaps off the car crashes to the floor.
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