Active Body Control Drive Carefully.....
My question is, what are the likely culprits? Pump was replaced at 54k and I have 112k on the car now. Otherwise I have no record of anything being done to the system.
If it really is coming from the reservoir, that's probably down to a failed accumulator. They go by different names, and have slightly different functions, but there's essentially four of them.
Its difficult to identify an individual failure with indirect trouble-shooting. You either need to remove or replace them one by one or all together. Not that difficult actually.
Did you notice any funny noises before it failed?
Nick




You can purchase the accumulators separately. Part for the front and rear accumulators (You need two) is: A220-327-01-15
Be advised there are two other nitrogen spheres in the system as well. One is mounted to the pressure relief valve (Part #A220-327-02-15) which is found in the front right side of the vehicle.
The other is a small nitrogen chamber (Called an Air Cell) that sits near the fuel pump in the driver side mid/center of the vehicle, (Part #A220-320-04-15).
You can take each one off, one by one and try to test for a punctured diaphragm, however at 100+k, the nitrogen starts to leak and reduce in pressure so it is a good idea to replace all of these units.
If one broke, another is not far behind.
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I was planning to replace the accumulators/pulsation dampeners anyway but I want to make sure that doing so is also going to solve my current issue. Financially I can really only afford to repair what is actually broken now.
Would bad accumulators force fluid back up and out of the reservoir as described?
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As long as the pump is pumping (clean) oil, it's OK.
If the leak every gets so bad that the reservoir is empty, don't run the engine.
Simply filling an empty reservoir isn't enough, as the pump is NOT self-priming. You have push oil into the pump under a few PSI of pressure.
But if the reservoir was never empty, you're OK.
Nick
This is what came up on Amazon for the accumulator:
I can't find the Pulsation Dampener or the Air Cell on Amazon......
Last edited by khutchinson22; Nov 2, 2015 at 10:17 PM.
Descriptions on internet vendor sites aren't reliable, and there's no information there to even tie it to a manufacturer. You really need to search by part number.
Try parts.com or mbpartsworld.
Nick
Last edited by Welwynnick; Nov 3, 2015 at 02:35 PM.
Thanks for all the help, guys!
People are quick to post horror stories about ABC, or any high-tech engineering for that matter.
Its much better to fix ABC than replace it, isn't it?
Nick







