Originally Posted by
thehemi
Setup: Stock '99 4.3 with Marine MPFI intake and MotoTron 60# injectors
Issue: Stumble when stabbing the throttle. If too quick, it can backfire. Same in Park or loaded.
I'm running stock exhaust manifolds now, but it was a turbo setup in the past. However, the stumble upon stabbing the throttle was always an issue, so I'm sure it's related to the intake/injectors. Otherwise, it runs great in all other situations.
Not sure if this suggests it's lean or rich, but I don't know how to adjust for it?
Thanks,
Scott