Typically that's an indicator to,
you know, check your ENGINE.
The Big Bang Theory Season 2, Episode 5
[ENGINE revving]
The Big Bang Theory Season 12, Episode 19
If you knocked I couldn't hear you.
I'm welding this locomotive ENGINE.
The Big Bang Theory Season 10, Episode 15
Does anybody know how to fix
combustion ENGINE?
The Big Bang Theory Season 4, Episode 19
[ENGINE RUNNING]
Breaking Bad Season 2, Episode 9