"Engine RPM" warning

[Monkey-wrench]

The "Engine RPM" warning often sounds at various airspeeds and attitudes for no apparent reason. Any ideas?

 

[tedbain]

I haven’t had this issue with the Dynon system but when I had VisionMicrosystems I had this exact problem and it was a broken wire from the RPM pick off to the data module that with vibration was giving intermittent connectivity.

 

[vlittle]

The first thing to check is the condition of the plugs and wires. Pay attention to the plug gaps as well. Any kind of misfire or preignition is a problem and will cause transient high rpm readings.