It's possible to over-rev an engine where as the rev limiter in the ECU can't control.
How? An example would be, if you were in 2nd gear at peak RPM and meant to up-shift to 3rd but instead found 1st. Mechanical over-revs may not cause immediate engine failure but can fail sometime later. Mechanical over-revs can cause the valve to kiss the piston, (float as a poster already stated) and one day, the engine eats a valve. Although this is not the only thing that can happen, immediate failure provides real-time feedback but it's the ticking time bomb fear that causes one to feel anxious.
For whatever it's worth, you now have to come to grips with either one of two things. 1) error in the dump file or 2) it happened
Just my .02
Last edited by ID2F; 01-15-2019 at 03:52 PM.