So, could the Accumulator be related to the car sagging?

I ask as I have no leaks, rebuilt valve block a couple of times(even switched solenoids sides left/right) replaced strut, & still have the front left sag after about a week!

 

Accumulators don’t lead to sagging, valve blocks do. Bad accumulators lead to lessened shock load, and bumpy ride . You have bad valve blocks

 

That's what I thought from the beginning. But I have taken them out/rebuilt a couple of times & even switched solenoids over, & still sags on the left front. The only improvement I made was, it had come to a point where it would start sagging after a few hours & now it starts after 5/6 days.

Not entirely sure I should buy a new valve block & have some other issue, as they are incredibly expensive.

Back to the accumulators; I have no warning lights coming up & the ride does not feel like there are any imperfections. The car is now 21 years old so read that they might better be replaced; would this improve the ride, or are they just good or bad & no in between?

 

I have front valve block for sale on eBay. 2005 SL55, took it off when I did coil over conversion. I assume it is original to the car. Message me if you are interested and I can send you a link to the listing.

 

Due to age of used valve blocks, I'm afraid to buy. Thanks.

 

Accumulators and pulsation dampeners are either good or bad, there is no "in between".

These devices are basically a container that has a rubber diaphragm in the middle of it. On one side, there is highly pressurized gas; the other side is filled with fluid from a connection to the ABC system When you hit a bump, an ABC strut compresses, forcing fluid into the fluid side of the container, compressing the gas on the other side of the rubber diaphragm. In this way, these devices absorb hydraulic fluid pressure spikes in the system allowing the suspension to perform more smoothly.

When they go bad, the rubber diaphragm gets a rupture and the compressed gas escapes into the system and eventually burps out through the ABC fluid reservoir. The accumulator/pulsation dampener fills completely with fluid, so it no longer has any ability to absorb those pressure spikes. So now, the ride is rougher, and the pressure spikes are beating on the rest of the ABC system - flexible rubber lines, struts, etc. This will cause these components to have problems much sooner than normal wear and tear.

Also, when that diaphragm ruptures, the gas on the other side is under very high pressure and it can cause bits of the rubber diaphragm to be pushed out into the ABC system, becoming lodged in the lines, or valve blocks, etc.... so it's really the best idea to replace these before they fail. My personal opinion, I'd replace them all if you've got 70K+ miles. If you wait until one or more fails, you're risking a much more complicated problem to fix. Think of these things like a timing belt; you don't want to wait until a failure that can cause bigger problem, you want to replace when you can reasonably assume they're getting close to the end of their life.

 

Agreed. My car only has 40K miles but is now 20+ years old, so was thinking would be good to replace the large front & rear Accumulators due to age.

Which I would like to do at the same time I replace the front valve block....just cannot accept the nearly €2000 cost of a new valve block!