Hi all, I'm trying to diagnose a possible ABC issue with my 2001 CL500, I have searched the internet for hints but no luck so far. My car started sagging on the right side front wheel and right side rear wheel (not equally) when left parked even for short amounts of time, sometimes I'd pop in a store and come back to see it dropped a bit of height already. Generally speaking, within a few hours to a day the right front wheel will touch the inside of the fender and the right rear wheel will have lost about half its height to the rear fender. The car pops right back up and the only warning on the dash is the ABC TOO LOW message prior to popping back up. No other errors when driving, etc.

I know you've probably read something like this on the forum about 100 times so far, I first thought it's the valves not holding pressure anymore and letting the fluid go back into the system but I then read there are 2 valves, one controlling the front wheels and another controlling the rear so that excludes my issue even though I have a rebuild kit on the way. To make things even more interesting and this is where I need some advice, if I do set the suspension height to the first setting (one red dot on the suspension button), the car stops sagging.

The short answer might well be a rodeo test but I'm unable to do that right now, unfortunately, I just moved into a new town with no MB dealership and I don't trust indies taking a guess on what should be replaced, I've thrown money out the window down that route before, I need time to find a proper shop but until then I'm trying to narrow it down. A bit of history on the car, 60k miles on the clock with a recent ABC flush done back in July so I don't think another flush would solve anything. I did have to change a strut on the left-hand side this year, could the other struts start failing as well?

Any thoughts? Why would the car stop sagging when the suspension is raised? I assume that excludes the valves losing pressure. Could it be the struts, but do they fail with a pattern like that? I can see no fluid dripping anywhere and the reservoir is at the correct level. I appreciate any thoughts you might have! Thank you.

 

Thank you bobterry99, I will start with the valve blocks, I have the seals on the way. Do I need to drain the system to take out the valves?

 

Got it, thanks!