I have a 08 FLHTCUI 27000 miles, with a Stage 1 cleaner, Vance and Hines True Duals with V&H tuner. I recently had a oil pressure and low engine performance problem. The dealer said the oil pump was not scavanging. The dealer replaced the oil pump and now it feels like the engine is down on power, especially below 3000 RPM. What should I check or do to get my lost power back?