Bonanza 36
Flight Crew Instrument; Flight Crew Private
Flight Crew Last 90 Days 12; Flight Crew Total 305
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Landed in Emergency Condition; Flight Crew Returned To Departure Airport
Aircraft
After departure from ZZZ on a southern heading; climbed to 8;500 feet with flight following to ZZZ1. After transitioning to cruise at 8;500 feet I realized my manifold pressure readings were significantly below expected (mid-20 in while expecting 30+). I informed Approach about turning back to ZZZ. The landing was uneventful. After rolling off the runway I was able to reproduce the lack of full power when opening the full throttle.
BE36 pilot reported an engine malfunction in flight resulting in a return to departure airport.