I am battling lean spikes while cruising 16.5-17.0 AFR, my set up is 99 silverado 4.3 5 speed with 52/65 T04E turbo 8 psi, p59 ecm swap, running closed loop speed density, marine intake 42lbs bosch injectors, ti automotive 450lph pump, boost reference regulator, catless straight 3 inch exhaust, it only does it while cruising between 2000-2500 rpm, lean spike happens OL and CL, I have swapped out several parts trying to find the issue with no luck, dont think its in the tune. I have tried adding fuel in the cells I cruise in but just makes it richer. Any insight would be appreciated. I attached tune file will try to get a log to attach.
silverturdo clsd.hpt