At full load WOT or even probably 60-75% throttle I get a pulsing/bucking experience that makes it awful to drive flat out. Im aware of the "3800 RPM Hesitation" thing, but I wouldnt describe this as a hesitation. My gut tells me its the secondaries due to it happening largely above 4000rpm, and I dont experience any misfires at any other time. Im able to free rev without any hiccup. As far as ive noticed AFRs have been fine, though tbf I havent noticed the reading during this pulsing experience. If I gradually climb RPM I dont have a problem either. FWIW, since my friend removed my cat, i know my 5/6 ports are inop right now, so I expected some power loss, but even that I have a hard time fully believing that would cause the pulse. Any ideas before I get in too deep?

 

A few things to look at:

Like you said, secondaries. If they were to not kick on, you will lean out. Check the injectors themselves and the wiring. Any idea when the last time the fuel filter was replaced?


Also verify your timing per the FSM. Make sure the timing advance works

 

It just occured to me that I have an extra set of injectors laying around that I will be trying. I can't speak on the fuel filter, but I do know that I personally have not changed it out.