check the line going to the charcoal cannister,if it is somehow hooked up so that you have engine vacuum on the tank all the time it could be responsible for noises in a all but empty tank.

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David S Poole
European Performance
Dallas, TX
4696880422

"Fortune favors the prepared mind"
1987 Mercedes Benz 420SEL
1988 Mercedes Benz 300TE (With new evaporator)
2000 Mercedes Benz C280
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