W221 stiff ABC ride
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W221 stiff ABC ride
Hello all
Proud owner of a w221 s500 with a 5.5 m273 v8
I have a issue, the car suspension feels very stiff
the car is equiped with ABC but when driving Slow it feels like I dont have any suspension at all. The feel is on al 4 corners, in comfort or sport
The drive feels stiff, on low speeds I can feel almost all things on the road. While driving fast on the highway, its less, but still quite harsh.
No codes are thrown. Flued isnt leaking (litterly no drop in over 6 months) and no strange noices from the car.
Flued level with engine on/off looks the same (the abc 'tank' is a tiny bit more filled than recommended, but the issue was even before I added the extra flued)
What do you think is the issue? Have the car just over 2 years, and it feels like its getting stiffer and stiffer
Maybe not important to forget, when the car is fully loaded, it gets less stiff. Not sure if that should matter, but its something that I notice
Proud owner of a w221 s500 with a 5.5 m273 v8
I have a issue, the car suspension feels very stiff
the car is equiped with ABC but when driving Slow it feels like I dont have any suspension at all. The feel is on al 4 corners, in comfort or sport
The drive feels stiff, on low speeds I can feel almost all things on the road. While driving fast on the highway, its less, but still quite harsh.
No codes are thrown. Flued isnt leaking (litterly no drop in over 6 months) and no strange noices from the car.
Flued level with engine on/off looks the same (the abc 'tank' is a tiny bit more filled than recommended, but the issue was even before I added the extra flued)
What do you think is the issue? Have the car just over 2 years, and it feels like its getting stiffer and stiffer
Maybe not important to forget, when the car is fully loaded, it gets less stiff. Not sure if that should matter, but its something that I notice
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222 S-65
OP it is time to plug into XENTRY.
Check ride height. If multiple ride height sensors are broken it will raise the car for stiff ride.
Also... Choice of tire and tire pressure are a big part of it riding nice.
Check ride height. If multiple ride height sensors are broken it will raise the car for stiff ride.
Also... Choice of tire and tire pressure are a big part of it riding nice.
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'13 s212 63 p30. '06 LX470
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Dont got xentry, but do got another scan tablet. Any thing I should look for specifically?
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I have replaced the pulsation dampener on the steeringpump before, and that made a weird sound. Does the same goes for the accumulators? Or should I see a difference in flued levels when the engine is on/off?
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"another scan tablet" isn't Xentry. Can this tablet access ALL MB modules?
Normally you would see a fluid difference, especially when the engine is running. The fluid level in the reservoir will drop to below the "engine running" mark, but still return to the full mark when engine is not running. This, of course, providing the volume is correct.
Normally you would see a fluid difference, especially when the engine is running. The fluid level in the reservoir will drop to below the "engine running" mark, but still return to the full mark when engine is not running. This, of course, providing the volume is correct.
Last edited by Sathinas; Sep 1, 2025 at 09:59 AM.
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"another scan tablet" isn't Xentry. Can this tablet access ALL MB modules?
Normally you would see a fluid difference, especially when the engine is running. The fluid level in the reservoir will drop to below the "engine running" mark, but still return to the full mark when engine is not running. This, of course, providing the volume is correct.
Normally you would see a fluid difference, especially when the engine is running. The fluid level in the reservoir will drop to below the "engine running" mark, but still return to the full mark when engine is not running. This, of course, providing the volume is correct.
And what you say, when the engine is off (lets say 4 hours) and I start it up, the fluid level should be lower than normally (compared to the engine on / off flued level) if one of the accumulators is bad, thats correct?
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S65
Nothing beats Dealer lever diagnostic tools. Sure, a lot of third party tools come close, but for specialized crap like this...
If the engine is off (4 hours, if you will), and you check the dipstick, oil level should be at the "full" mark, or the top indentation.
Once you get the engine going, and give it a few minutes, you can check the level again and if all is good, the level should be at the lower indentation. If you have blown accumulator(s), then the level will likely be below that "engine running" level mark, because there is not more fluid entering the accumulator(s) and filling the void where the pressurized bladder's nitrogen volume used to be.
If the engine is off (4 hours, if you will), and you check the dipstick, oil level should be at the "full" mark, or the top indentation.
Once you get the engine going, and give it a few minutes, you can check the level again and if all is good, the level should be at the lower indentation. If you have blown accumulator(s), then the level will likely be below that "engine running" level mark, because there is not more fluid entering the accumulator(s) and filling the void where the pressurized bladder's nitrogen volume used to be.
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S500
an accumulator is what gives, the give - its a ball with a diaphragm stretched between the two halves - then one side pumped to silly PSI with nitrogen, then at far lower pressure they put fluid on the other side - for brakes you fill it right up and then have a ball of high pressure fluid, press the pedal and you release the pressure to apply the brakes with no effort 747s Citroen's and and RR been like that since the 60s
I guess must be something like on the ABC cars you part fill the sphere, the more you fill that can stiffen the suspension, lower the pressure and the diaphragm gives more compliance - but once its split there is no leak - its all internal (level would drop a bit) but was likely topped up at service years ago - and the fluid dead ends in the sphere with no squidge left and a brittle ride ?
they are service items fluid change every 4 years min and spheres every 60k miles ?
I guess must be something like on the ABC cars you part fill the sphere, the more you fill that can stiffen the suspension, lower the pressure and the diaphragm gives more compliance - but once its split there is no leak - its all internal (level would drop a bit) but was likely topped up at service years ago - and the fluid dead ends in the sphere with no squidge left and a brittle ride ?
they are service items fluid change every 4 years min and spheres every 60k miles ?
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From: USA
Hello all
Proud owner of a w221 s500 with a 5.5 m273 v8
I have a issue, the car suspension feels very stiff
the car is equiped with ABC but when driving Slow it feels like I dont have any suspension at all. The feel is on al 4 corners, in comfort or sport
The drive feels stiff, on low speeds I can feel almost all things on the road. While driving fast on the highway, its less, but still quite harsh.
No codes are thrown. Flued isnt leaking (litterly no drop in over 6 months) and no strange noices from the car.
Flued level with engine on/off looks the same (the abc 'tank' is a tiny bit more filled than recommended, but the issue was even before I added the extra flued)
What do you think is the issue? Have the car just over 2 years, and it feels like its getting stiffer and stiffer
Maybe not important to forget, when the car is fully loaded, it gets less stiff. Not sure if that should matter, but its something that I notice
Proud owner of a w221 s500 with a 5.5 m273 v8
I have a issue, the car suspension feels very stiff
the car is equiped with ABC but when driving Slow it feels like I dont have any suspension at all. The feel is on al 4 corners, in comfort or sport
The drive feels stiff, on low speeds I can feel almost all things on the road. While driving fast on the highway, its less, but still quite harsh.
No codes are thrown. Flued isnt leaking (litterly no drop in over 6 months) and no strange noices from the car.
Flued level with engine on/off looks the same (the abc 'tank' is a tiny bit more filled than recommended, but the issue was even before I added the extra flued)
What do you think is the issue? Have the car just over 2 years, and it feels like its getting stiffer and stiffer
Maybe not important to forget, when the car is fully loaded, it gets less stiff. Not sure if that should matter, but its something that I notice
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2006 W221 S500L M273
I don't know the history of the car, but my car had 2 bad accumulators and the fluid level was ok (probably topped off) and i never saw any ABC warning in the dash.
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S500
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2009 S600 V-12
Please see the link for MB ABC troubleshooting guide.
I saw a YouTube video a time ago and you unscrew a suspected bad accumulator, empty it out, lay it on its back, and insert a long skinny screwdriver into the neck and very easily (no force required or a good bladder will get impaled) slowing drop it into the hole about half way into the globe and rest on the bladder on good accumulator.
A bad bladder it easily falls through all way to bottom of the globe.
JR
I saw a YouTube video a time ago and you unscrew a suspected bad accumulator, empty it out, lay it on its back, and insert a long skinny screwdriver into the neck and very easily (no force required or a good bladder will get impaled) slowing drop it into the hole about half way into the globe and rest on the bladder on good accumulator.
A bad bladder it easily falls through all way to bottom of the globe.
JR
Last edited by johnnyrocket52; Sep 2, 2025 at 08:07 AM.
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'13 s212 63 p30. '06 LX470
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Yeah allright, I guess I got the same issue.
If i recall correctly, there are 3 accumulators right?
1. On the powersteering pump
2. Behind the front bumper
3. In the trunk on the driver side
Which did you replace? If there are more, please tell me also
If i recall correctly, there are 3 accumulators right?
1. On the powersteering pump
2. Behind the front bumper
3. In the trunk on the driver side
Which did you replace? If there are more, please tell me also
