boosted vr coupe

just recently installed a custom intake manifold ona friends obd1 h22 eg.... the problem were having is that only at part throttle(10-20%) the motor hits a fuel cut at 1500rpm... we were datalogging and noticed that at that rpm the fuel injector durations and duty cycles were at zero... our wideband also read 0... this makes driving the car normally nearly impossible withous the car hitting the "rev limit" while in gear casuing the car to buck voilently.... any ideas?