I've noticed something that might be a problem, or might be leading to one, and was wondering if anyone had any ideas on the cause....

During high power run-up my rpm reading on the EC2 sometimes "bounces around".  Rpm reading is always steady at 3500, and at 5500 or whatever in flight. Sometimes, when I increase throttle during runup it'll get to around 4500, then it'll start changing reading rapidly (2 or 3 times a second) between 4500 and somewhere above 5000. Other times it'll sit still at 5300 or so. I don't see any performance change. I know the rpm is powered from injector pulses. What could make the injector pulses bounce like that?

John Slade
Turbo rotary Cozy