Post up on a chevy tbi swap forum and maybe someone can help you figure it out.
'91 Bronco 351w, ZF5, D44 TTB, 9" rear swap with disk brakes, 37" toyos, method wheels, mastercraft seats, A/C and heat
Or massive pre o2 exhaust leak....
Ryan Clarke
(214)695-7901
mine had been running like **** lately. it would start up and run fine, but under load it would stumble/miss/act like it wasn't getting fuel. once i determined it wasn't out of gas, i thought the paper in the fuel filter had come loose and was plugging up. replaced, no fixy. fuel pressure is 9 psi according to the gauge, kinda low. before i fukt with the fuel pumps, i thought i'd look at the cheap tune up stuff. warrantied out my wires since battery acid ate parts of them, new cap, cleaned rotor, etc. pulled out the plugs to see if they were fouled, they looked great. i replaced them when i did tbi. still stumbled. jacked with a few other things and checked for loose wires. decided to pull plugs again to replace with new ones. this one crumbled into pieces this time when i pulled it out of the socket. probably was leaking spark under load.
new plugs in. runs great again. least i didn't fag out and put a carb back on it.
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