Ignition Problem ?

[ExplodingGopher]

Ok this just started recently with my 5.0. At WOT the car takes off great but once it hits 4,000 rpm or above it stutters like mad and backfires like hell. Got a new dist cap and rotor < Accel. and checked the wires which are fine, no arcing at all. Could this be timing? I am replacing the fuel filter tomarrow incase the old one is clogged and starving the engine at WOT. Specs in sig.

 

[jrichker]

High RPM miss on a warm engine is usually associated with a failing TFI module.

 

[ExplodingGopher]

What is a TFI module and what does it do. how much is a new one.
("Who is your daddy, and what does he do." -Arnold S.)

 

[HISSIN50]

TFI is on the side of the dizzy housing.

what are your plugs gapped at? you could simply be overrunning the plug gaps (though i agree in full with JR, im trying to think of something simple and cheap to check first).

good luck.

 

[90pony302]

definitely check the little things first. Plugs, wires, cap and rotor....which its sounds like you did already. Autozone can check ur tfi module for you. Other things to check would be coil, pickup in the dizzy(cheaper than gettin a new tfi). Also i think the zone quoted me like 65 bucks on a new tfi.