fireman685

I'm typing this from my phone and can't find my glasses so pardon any spelling or iPhone auto corrections haha.

My left rear strut begins to sag as soon as I shut off the engine. I've had the valve block out twice and orings replaced twice by someone who knows what they're doing but it still does it. The ABC Visit Workshop warning will appear ONLY after the car has warmed up and comes to a complete stop for about 10-15 seconds. STAR says its detecting movement in the strut when stopped thus warning appears. I did not show up as a hard fault though. Pump is good at 180-185 bar. There are no obvious leaks around the strut itself either.

So. Because it's bleeding off pressure immediately after shut off indicate a bad block for sure or can the strut be bad and NOT have an external leak?
Solenoids opened/closed fine when voltage applied to them.

vmystikilv

My Vote is bad strut.

fireman685

Let me add a little more info I forgot to mention. Prior to pulling both blocks the left rear would sag overnight. Afterwards it would start to sag as soon as I killed the engine. In about 5 minutes or less it was more than noticeable. I did not get a Visit Workshop warning either prior to block rebuilds. When both blocks were out I replaced all four accumulators. The two big one were obviously blown with the smaller two questionable. One of the big ones blew just prior to pulling both blocks as I suddenly started getting warning dings over every bump and the car rode like hell. I parked it the same day. It's an 05 CL55 AMG Pump is Ixetic not Luk so replaced after 2009. Current mileage is 81k

I'm wondering if I'm in that "fixing one problem exposes other problems" cycle haha.

vmystikilv

This is quite an expensive game to play if your playing by those rules with this system. Reading the thread it sound like you replaced mostly everything already. The only other option is Condiluted.


The mechanic would have had to rebuild the block wrong twice, or there is still and underlying problem with it that a simple ring job wont fix it and you still need to buy a new one.


I assuming you have a good mechanic, so, only thing left is to replace the strut.


Then again, I have met mechanics that say they know everything about the car and simple questions about the ABC system leave them dumbfounded. If I know more about the system then a mechanic does, there's a problem....


Instead of playing this expensive game, it might just be worth it to pay Mercedes the diagnostic to find out what's wrong. Then, bring it to your mechanic and have him fix the culprit.


Gambling man, I would be a new shock, sensible man, I would bring it to Mercedes, have them tell me its a bad shock, order from arnott, then have mechanic install.




Good luck man, I hope you fix your car..


P.S. Ever thought about just changing everything over to coils then you would never have to worry about this again. You can then sell your old parts and recoup most if not all the cost plus some back

fireman685

When I bought the car the plan was to enjoy abc till a major failure then get rid of it but I like the system so much I'd like to keep it as long as possible. A pump failure will be the end of abc for me though and as of now it's good. It was putting out a little over 180 bar.
Everything I read about a bad strut involves a leak. Mine is not leaking but I can't help think that maybe something internal that is the problem. STAR would not point to either one as an exact culprit. It just said it detected strut movement at standstill or something like that.
The person who rebuilt the blocks is a forum member who has done many with no issues and has his own SDS. One solenoid has a potential issue. When the piston was slid out and the cylinder inspected with a magnifying glass, the area where the piston seats inside looked like it had some issues as it was not like the others. That's the only way I can describe it.
I'm going to start with the block first and pick up a used one. It's become quite easy for me to remove the rear valve block now haha. Takes less than 10 minutes.

MagCL

I've never had to change an abc strut yet (knock on wood!!) so I don't know how hard it is or how long it takes but maybe if it's not that much work, switch the back two around from L to R and vice versa to determine if its the strut.

Is it possible to pressure test an abc strut to see if it holds pressure??

awiner

I thought about that too, then checked EPC. According to EPC there is a Right Rear and a Left Rear. Both with their own part #'s. They aren't interchangeable.

fireman685

Well I'm going with another valve block. I just paid a forum member who deleted his abc in favor of a custom air set up. He has the newer part number so going to give it a try. If that don't work I'll pick up his left rear strut then too haha.
Hope to get before the end of the week and it won't take me more than 30 minutes to swap them out. I'll keep yall posted.

biker349

if i were you i'd get the strutts from china rebuilt. they are probably cheaper than most used, have a 1 year warranty and in my experience ship quickly, within 1 week.

vmystikilv

2nd that

fireman685

It was the valve block. Bought a good used one from a forum member and then problem seems to be solved so far.

OCKlasse

vmystikilv

That's great, glad your back is back to normal. I hate repair situations like that. You had said the mechanic had already fixed it twice. Glad you went with you gut and found the problem. I'd get my money back on the valve repair job if you can. Enjoy the ride and welcome back to the open road

fireman685

It's all good. It was a forum member who did the work and he's made good on everything.

Welwynnick

I wouldn't have guessed that was the cause. Good job, and good persistence with ABC!

Nick

OCKlasse

If the strut isn't leaking and the car is dropping after the power is off, it has to be the valve block. The system can maintain enough pressure to keep that corner raised when the car is on but as soon as the pump is off, the fluid escapes through that corner's valve, whether it has to do with the seal, the valve itself, or whatever.