Thats not what I was trying to do.. you must understand that the local Mercedes tech is 80mi away.. so I tend to depend on the limited knowledge of the local techs..so with my limited time and knowledge base I have to make the best decision I can... the only things I did replace were the fuel distributor because this town is notorious for bad gas.. replaced the ovp relay because it was hot to the touch.. and regular maint parts i.e plugs/wires cap/rotor.. there was/is good pressure from the pumps and to the distributor the hoses are ok at the idle control valve.. cleaned it car runs much smoother..fuel pump relay was tested and found to be in working order.. there was an attempt to correct the mixture as best the tech could because all of the things you mentioned were tested.. the expense is not such an issue as the cars are underestimated in this part of the countras far as their value so parts are kinda cheap.. next time I will spell out the testing done a bit more.. again I have not been throwing parts at the car.. I am very far from assumptios and reactionary.. I have literally hundreds of hours spent dxing the prob and 3 sepearate visit to local shops testing every obvious link in the "chain" leading to a better running car..if I were throwing parts at the car it would have taken much less than the 5 mos its taken to achieve the limited amount of "success" I have