2001 s500 ABC suspension
 

Hey guys
i have a 2001 w220 with Abc i bought it and it was front end accident
i replaced the valve block front one and two hoses and fill the fluids started it was really good when i started in my garage every thing works normal no messages no errors but when i took it to test drive and i have an issue with it it sounds strange to me when i drive it either front or reverse the car start going down from the right rear suspension and i get a red message " stop.. car is too low "
when i break the car goes back to normal level and the message disappear
press the gas and drive it is doing the same thing going down from the rear right corner and the message comes back
i did bleeding to the system and check for possible leak found NON
so if any one has an idea what to do
thanks

Could be either a shot accumulator of that particular corner, or sticky valves in the rear valve block. If you have access to an OBD code reader (or better Star diagnostics), the stored codes might help. Though I haven't test it myself, a suggested test for shot accumulators is to push down on the suspected corner when the car is not running (so push on the right rear part of the trunk for example), and if there is no travel in the strut, all is well. In case there is some travel, that indicates that the accumulator is not able to hold pressure, and the pump is making up for lost Nitrogen in the accumulator by pumping in Pentosin. For troubleshooting the valve block, I don't know of an easy way - perhaps more experienced members can chime in.

Sorry, that doesn't test for bad accumulators. When the car is not running, the valve blocks isolate the struts from the supply and return loops, so the accumulators are not connected at all. All you feel are the steel springs.

The best way is to look at the change of oil level in the ABC reservoir. It should be at the upper mark with the engine off for some time, and at the lower mark with the engine running (and the accumulators charged up). If the variation is different to that, then one or more accumulators are shot.

Nick

Thanks for the correction Nick! :)

If it's fine when braking but the problem comes back when you give it the gas, sounds like a bad electrical connection

thanks guys
i tried check the fluids level while engine running and when it is off and i found the level is above normal when the car is off but when it is running the level goes down but still over the mark looks like i overfill it
any how while i am trying to do that checking level the four suspension went down and i got red message" car is too low " and never go up again
so i will try give it a help by raise the level using floor jacks and try
and i heard sound like air when the car trying to level it self so that is another thing i need to check it might need a bleeding a gain but i need to know what is the best way to do bleeding
and i have question about the star diagnostics is it worth it to buy one
and where i can find good deals on those and iif there is a used ones for sale or not
TUSABES you might right cause when i put the new valve block tow of the plugs connectors where broken and i connected back
so that is another thing i need to try
let you know ...

I didn't see you say you removed and cleaned the rear valve block. Do that. The rear valve block might have some junk in the valve that is supposed to let pressure flow over to the right rear strut when requested.

And are the cracked connectors on the front valve block? Or the rear? And are the broken bits from the wired end or the part on the valve block? You can easily rewire new connectors to the ends of the signal wires. You can remove the pins from the back with a connector repair tool and reinsert into fresh connector bodies, or go with the old clip and rewire, if you are comfortable with splicing electrical connectors to wires? Get replacement connectors, note the polarity of existing connection, snip off old, bit of heat shrink tube slid over the wire, rewire new, bit of solder, tape each wire splice, slide heat shrink over the repair and heat it, bit more tape.