The brake pads being worn should not effect the power output of the engine unless they are dragging, ensure your car will roll down a small grade easily while in nuetral, that will tell you if there is any drag. Also what brand of filters did you use? If other than MB filters that can cause restriction and therfore reduce oil pressure and flow of fuel. If not MB filters replace with genuine MB ones. If so, then you may have a clog, also if you used spark plugs that are not recommended for that engine that could cause a fuss with your ignition. Make sure you got the plugs that MB reccommends. Good luck!
Brian

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Brian W. Heitman

www.MBCA.org/northtexas

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