Should I worry about ABC failures!
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Joined: Aug 2018
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2001 CL600, 2002 Bentley,1969 Mercedes 280SL, 1993 Mercedes 400SEL
Thanks Nick for your response, That is the exact noise I have. The problem is Mercedes emailed me a diagram showing me the accumulators on my car (2001 CL600). There are (3), one in the center back, one by the fuel pump under drivers door, and one in the front left wheel well in front of the tire. Maybe it is reversed because this car being from the US is left hand drive, What do you think? Also Concretebrew on this thread has mentioned this problem which again is the exact symptom and his was the ABC line that runs from pump to back shocks, it was rubbing somewhere on the transmission and finally burst. He had replaced everything until he replaced the line and it went away. My car has 112,000 miles on it, in the last 41/2 years I have spent about $12,000.00 in repairs, new struts front end, 2 coils, voltage modulator, etc. This whine started about a month ago and is driving me crazy. I love the car and I love the V12's ( also had V12 Jaguars) for their smooth strong motors, but this whine is killing me.
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Joined: Nov 2010
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From: Welwyn, Herts, UK
2006 S600
Are you sure there are only three on your car? There are usually four, and the fourth should be BEHIND the right front wheel, attached to the pressure regulator. This one smooths the pressure pulses coming out of the tandem pump (until it wears out).
The accumulator in FRONT of the left front wheel sits on the front valve block, and is the dynamic reservoir for the front struts.
The accumulator by the fuel pump under the rear seat sits on the rear valve block, and is the dynamic reservoir for the two rear struts.
The first one, the pulsation damper, which sits behind the front wheel, is the usual cause of the "transmission while" type sound.
Nick
The accumulator in FRONT of the left front wheel sits on the front valve block, and is the dynamic reservoir for the front struts.
The accumulator by the fuel pump under the rear seat sits on the rear valve block, and is the dynamic reservoir for the two rear struts.
The first one, the pulsation damper, which sits behind the front wheel, is the usual cause of the "transmission while" type sound.
Nick
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2001 CL600, 2002 Bentley,1969 Mercedes 280SL, 1993 Mercedes 400SEL
Thanks again Nick, my friend at mercedes said the 2001 does not have a pulsation damper, Also Nick my car makes the whine even with the belt off according to my mechanic just like concretbrews car.
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2001 CL600, 2002 Bentley,1969 Mercedes 280SL, 1993 Mercedes 400SEL
Hi Nick, my friend from Mercedes did call me back after I sent him your diagram, he said there is a air reservoir behind the passenger side wheel well. Is that what you mentioned?, he said its $155.00 to buy, thanks, do you still think it could be that even if the noise remains even with the belt removed? Please let me know, thanks, Jeff Sorry Nick I noticed on previous threads written by you that if the noise goes away with the belt off than it is most likely an accumulator my whine dosen't go away with belt removal.
Last edited by Jeffrey Miller; Dec 30, 2019 at 07:51 PM.
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Joined: Aug 2018
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2001 CL600, 2002 Bentley,1969 Mercedes 280SL, 1993 Mercedes 400SEL
Thank you, Thank you, and Thank you again Nick, You were 100% correct , it was the accumulator behind the right front wheel # 220 327 02 15, 10 minutes and it was in, took the wheel off and it was right there. Nobody could find where the noise was coming from. Your thread saved me a lot of unnecessary work, time, and money. Thank you again Jeff
