Don't know. Its in the factory service manual. MB sure didn't go through the extra work and updates to add a secondary fuel pump without reason.

It may only affect a minority of vehicles under certain circumstances -- but that is why our vehicles are quality.

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2016 Monsoon Gray Audi Allroad - 21k
2008 Black Mercedes E350 4Matic Sport - 131k
2014 Jeep Wranger Unlimited Sahara - 62k
2003 Gray Mercedes ML350 - 122k