I have a 92 f150 4.9 5 speed manual rough idle, stumbles a bit when accelerating. I have replaced MAP, TPS, ICS, EGR valve, and the EGR positioning sensor. The truck has new fuel tanks and fuel pumps and nothing has changed. It is running rich and is using twice the fuel as normal. Is it possible the ECM is bad?

 

Hard to say. What fault codes did you get from the Key On Engine Off test before you starting throwing parts at it? What codes are still coming up and what are the fuel pressures at idle and when driving? How long has it been since a new cap, rotor and plug wires have been installed?