Intermittent power loss

Truck is '95 cc a/t XL with 125,000 on her. I recently purchased it to push snow as that is what it is set up for previously. Truck ran rough when purchased and Autoenginuity Read good on buzz and cylinder contribution. It still missed and buzz was weak on #3 so after pulling valve cover and replacing burned gasket and wiring she buzzed bad on 3 and showed injector code. Replaced defective inj. All this time she read EBPV codes and seemed starved for power.

My upgrades on this truck previous to the inj. were 6637 filter and 3" straight pipe cat and muff delete. Live data on A/E reads 36-37 psi. on EPBV while my '96 reads 14psi. At times with 140 IDM on her she runs great other times I can't pass slower traffic and this is with the EPBV unplugged, she ran worse plugged up and consistently smelled hot. I do not have exhaust temp gauge yet.

Any suggestions what to look for? Thanks for looking.