Trouble_Maker

i have a 99 4.6 triton...when driving, cruisin at around 55 mph truck miss fires sometimes a little sometimes more than a little...i changed one of the coil packs and no change.
i'm hoping it's not the fuel pump tappin out but, i don't wanna change it and find out thats not the problem...n e help is appreciated...david

Dirtbuster1

Have you thrown any codes yet? What led you to change the coil pack that you did. It's been raining alot all over the country lately, causing all sorts of problems with coil packs!

droptopfox

check the injector wires a loose connection will cause that

Trouble_Maker

was puttin out a code, wouldn't hardly idle jus settin in the driveway so, after i changed the coil pack it straightened rite up except it is still has this miss around 55 cruisin speed...idk just hope it's not the fuel pump.

Trouble_Maker

u think a clogged injector or maybe a dirty fuel filter could or potentialy a fuel pump going bad cause this issue?

Trouble_Maker

bump

droptopfox

yes i do but my budddys did the same thing he pulled the injector plugs checked them all they were a little screwed up so he cleaned them alittle dielectric grease plugged them back in and it was fixed

Good old Bill

You need to verify fuel pressure during the engine missfiring, poor pump pressure or even a plugged fuel filter will cause the entire engine not to opperate properly not a true missing condition. Injectors or even old plug wires can be the cause.

Trouble_Maker

yur buddy should play the lottery! thanx bro

Trouble_Maker

i was thinkin the same...thanx bill

i was wondering! since the enguine drops cylinders as the truck accelerates, if what ever tells the enguine to do that would have something to do with these hicups?