miss firing 4.0ltr need help

[Banger91]

I have a 91 ford explorer with a 4.0ltr that feels like it is missfiring. I have check compression in all cylinders and they are all with in 15psi, Replaced the computer and coilpack. Spark plug #5 was black and smelled like fuel, the rest of the plugs looked good. It's got plenty of vaccum. DO you guys Think its time to check fuel pressure??? and if so what would I look for?

Thanks
Austin

 

[twoll86]

I have a 91 ford explorer with a 4.0ltr that feels like it is missfiring. I have check compression in all cylinders and they are all with in 15psi, Replaced the computer and coilpack. Spark plug #5 was black and smelled like fuel, the rest of the plugs looked good. It's got plenty of vaccum. DO you guys Think its time to check fuel pressure??? and if so what would I look for?

Thanks
Austin

try swaping the ignition conrtol modular(edis) its behind the battery on the radiator support it controls ur spark. mine went bad and exploded the coil

 

[modelageek]

I have a 91 ford explorer with a 4.0ltr that feels like it is missfiring. I have check compression in all cylinders and they are all with in 15psi, Replaced the computer and coilpack. Spark plug #5 was black and smelled like fuel, the rest of the plugs looked good. It's got plenty of vaccum. DO you guys Think its time to check fuel pressure??? and if so what would I look for?

Thanks
Austin

at a minimum change the fuel filter and check the vacuum line on the fuel pressure regulator

 

[Big Jim M]

Cap, wires and new Motorcraft plugs are in order here. ONE plug looking different and wet means, most times, a bad cap, a bad wire or a bad plug.
Big JIm

 

[Banger91]

Cap, wires and new Motorcraft plugs are in order here. ONE plug looking different and wet means, most times, a bad cap, a bad wire or a bad plug.
Big JIm

It's got a coilpack tho

 

[snoman6115]

then most likely TPS or jsut try cleaning sensors, like maf and such