i have a 2003 clk 270cdi,i recently removed the egr to clean it,when i refitted the egr the management light came on,i have purchase a carsoft i980 and deleted the management light but it comes back on a few miutes later and the code reader states egr valve fault,i am now doing the egr delete however i am not sure how you test the maf for a signal feed,i have had the resistors made up for me so can anyone explain how i check the maf for a signal feed.
