Evening all, My 2003 C5 2.0 HDi has been playing up, lack of power, lost 10mpg of the urban average, lots of black smoke out the exhaust etc. Local garage diagnosed faulty MAF from the error code. I replaced the MAF no change. Having studied the forum I've disconnected the vacuum pipe from the maual EGR valve and this have improved. There's no cable at the EGR so would it have an error code? The vacuum pipe has suction present at tickover, could this mean the control valve's goosed? Many thanks