It is the fuel sender. The contacts between the float and wire is flaky. You can access it from the trunk but you need a 46mm socket. I normally open it up and soak it in engine cleaning agent and brush off all the crap inside the tube. The wire is delicate so need to be careful. Good luck.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
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1 x 87 300TDT wagon
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