Also I have to wonder, thought MS/Asobo are against there aircraft being modded. They still see the mods that were released for the DA’s. And Beechcraft 18 as fixing stuff for them. So why bother.
So just bumping this as it’s still an issue in MSFS 2024 - including the most recent SU4 beta 
LOL 4 years later and it’s still bugged. Red lining and flashing at 2300 RPM right now as I fly the DA40.
msfs-2024 tag added 
Actually I was shocked to load it up and find that it doesn’t redline anymore except briefly at full power - presumably before a governor kicks in. I dunno when this happened, but I reloaded everything and tried again, and it’s fixed for me. (SU4 beta)
Ooh! Will have to check it out in this current build.
Created with love, coffee and migraines by yours truly
As mentioned by @TheBlackWind977 also fixed for me in FS2024:
Nevertheless need to check for FS2020.
Edit: FS2020 still have the issue (recent SU4 updates were only for FS2024).