Southern Interior Flight Centre-Cessna 172S-Power Loss

C-GSFR, a Cessna 172S operated by Southern Interior Flight Centre (1993) Ltd, was conducting circuit training flights at Kelowna International Airport (CYLW), BC, with 1 flight instructor and 1
student on board. During the second circuit, the aircraft experienced a sudden engine power loss (Avco Lycoming, IO-360-L2A) during climb out at approximately 200 feet AGL. The flight instructor
took control, declared a MAYDAY and pitched the aircraft forward in preparation for a forced landing. The flight instructor recovered engine power with throttle manipulation at approximately 75
feet AGL and climbed to 300 feet AGL. A second MAYDAY was declared and the aircraft landed without incident on Runway 16. ARFF was on standby. There were no injuries and no damage to the aircraft. The G1000 download indicated a fluctuating fuel flow with a drop to 1.08 gallons per
hour. Maintenance removed the fuel servo (Precision Airmotive Model RSA-5AD1) to inspect for intermittent operation.