This popped up along with the issue:
DEBUG : map::unboard_vehicle: vehicle not found
FUNCTION : void map::unboard_vehicle(const tripoint&, bool)
FILE : src/map.cpp
LINE : 1055
I guess you’ve disabled [c]ruise control in the vehicle control.
Other than that: I was unable to reproduce the described behavior in build 0.E-11157 64-bit on Windows 7 with default mods.
PS: It’s likelier to get someone to help you if you name game/build version, your operating system and active mods with a bug report… Otherwise it’ll be just guessing.
I’ve been getting this quite regularly on latest experimentals while riding motor boat. After the error appears, my char just stops at the place and the vehicles teleports from under her. Well, not teleports but it’s like it just rides through her without any interaction. Oh, and i definitely haven’t disabled CC. Well, it could happen once or twice but not >half a dozen times.
Sadly, it doesn’t seem to be reproducible.