i have a 90 5.0 and am dealing with a misfire. it will sit at idle now but u can hear the motor misfire. now i have changed the plugs, wires, dist cap, fuel filter, fuel injectors, mass air flo sensor, egr valve (whole assymbley) did a compression test, and i still have the misfire. what else would cause the misfire? need some help on this one.

 

FP test, EEC1V test, Cyl BAL test, then post results. Will get help from there.

 

what firing order did you use and what plugs did you use ?? what gap as well

 

the firing order we used is 1 3 7 2 6 5 4 8, the plugs are ford motorcraft (asf42c) we have them gapped at .054.

 

Firewall
4 8
3 7
2 6
1 5
Front bumper
set the firing order with the plugs numbered like this?

Also what exactly do you mean by misfire, misfire to the point it can't be driven, just at idle. How does (if it does) the car accelerate, does it clear up in the high end? whats your base timing set at with the spout unplugged?