What type of a/c was that?
I've been in a
Jetprop and flown a
TBM850 for 1.5hrs but never smelt anything.
I know CO doesn't smell but if exhaust was entering the cockpit then CO would register on a decent meter - unless you are running peak-EGT or LOP in which case there shouldn't be any, but you won't be doing that during high AoA flight.