I have reached the end of my rope with this truck.A cracked ex manifold and leaking valve coverled to;
new
plugs
cap @ rotor
fuel filter
shorty headers
under drive pulleys (crank and water pump)
upper to lower plenum, t body, egr, and iac gaskets
cobra 1.7 bolt down roller rockers (properly adjusted to 24 fp @ 3/4 turn past 0 lash)
custom true dual exhaust with no cross over, after market hi-flo cats with no mufflers.
cleaned the k&n fipk.

At this point the check engine lite started to come on intermittently. Got codes for;
egr not closing properly,
o2 sensor out of range always lean.
Truck also intermittently high idles, idle surges, and bucks under low rpm low load. It has black carbon at the pipes, but smells more hot(like gun powder/foundery/grinding fumes) than raw fuel.

So far;
new
egr valve
egr valve position sensor
egr control valve
egr tube (from egr valve to intake)
IAC valve
tps sensor
O2 sensor (local parts store, not ford )
checked for vacume leaks, lose hoses/wires, ground connections (all at least three times).

NO CHANGE IN THE PROBLEM. The truck has great power, starts good, and other than occasional bucking at low rpm low load has good drivability. Please Help Me before I burn this sob to the ground in the driveway!

I am begining to believe the computer can not cope with the added air flow of the filter/ exhaust/ rocker combo.

Any opinions/ advice would be greatly appreciated!Thanks
Adam
PS e-mail @ aroot1@peoplepc.com and mention in the subject that it is about the truck so I don't delete as spam if u can help.