The AIR pump only pumps until the engine/cat is warmed up. And when it is, it has no effect on engine performance, it's after the fact. As Pete already stated, the electric motor is low draw. If you noticed a slower takeoff with the pump running, and that low power draw was the cause, your charging system must be suffering and affecting your ignition. But logically, your pump was on because the engine wasn't up to running temperature, which does have an effect on performance. The pump wasn't the cause.