Hello. I have currently problem that 80hp 912A3 is runing a little bit rough when I fly on cruise.
Its sounds like sometimes missfire - engien is running good but from time to time I its signle shake every 0,5-1 min. All problem is always gone when I switch on carburetor heating (airbox) starts run super smooth.
I assume that without heating engine gets more and cooler air and with less air (no ram efect) so seems that mixture is loo lean....
I had this problem with 3 other 912 80 hp - diferent versions, one brand new. Exactly same behaviour.
Main jest is 1.55, carburetos overhauled and synchronized.
What it can be?