hi
my 2000 4.6 4x4 was running good then the other day the ses light came on started running rough. i ran a scan it showed codes for missfire on cyl. 3,7 and 8 ,also lean fuel on bank 2
i changed the fuel filter the plugs, check fuel pump pressure checked the cop's.cleaned the egr ports one was a 100% clogged the other about 40% clogged i cleaned the iac. still running rough, if you unplug the egr valve vacum line it runs alot better but not right. when accelerating it surges till it gets up to about 50 mph,i can here hissing when the egr vacum is plugged in not when unplugged,checked the line for cracks,
any help would be great.
could it be maf or egr selonoid
thanks