ryan_89_mustang

Alright since I have had my car there has been a random miss. It is not constant it has no rhythm to it or anything. It is very noticeable at idle because the car and shifter shakes and you can hear the dead note in the exhaust. If I go WOT I don't really notice it but I'm sure it is still there.
I have replaced the plugs, wires, cap and rotor so far. I was thinking it could be the coil maybe? Anyone have an idea? Thanks

kennebell92conv

koeo test and koer test to see if has codes

TrimDrip

go ahead and run the engine balance test too.

ryan_89_mustang

Yeah i ran it and I'm getting nothing except for my egr and emissions junk which it not functional so nothing.

ryan_89_mustang

I did that as well and i get different cylinders every time.

TrimDrip

when the last time you put o2 sensors in?

ryan_89_mustang

I haven't but it has a miss in open loop too. It doesn't seem quite as bad until it warms up to operating temperature though.

TrimDrip

you never had trouble with it not wanting to start?

TrimDrip

a guy that works with my mechanic has a chevy truck (bare with me) that is having the same problem. They put the tester on it and it shows multi-cylinder missfire. He has tried plugs, wires, two distributors, coil, ignition, computer, crank sensor, fuel filter, fuel pump, fuel pump relay, new injectors. The fuel pressure is in spec.

He is now wondering about the 02 sensors.

His truck won't even crank sometimes in the morning until he bumps the fuel pump relay. Hell, the thing may have corroded wiring for all I know.

ryan_89_mustang

Starts perfect when cold. When hot when you start it, it will start then surge low and die really quick then start it again right after it dies and it will start and idle fine.