I Think It's Accepted Within The Fandom That Revving Engines Is What You'd Think It Means - Tumblr Posts

Hc that any Cybertronian with a car, truck, or ship alt mode can voluntarily beep or honk in robot mode

And that some of them with really loud ones would sneak up on others from behind and HONK to spook em

Just thinking about what if Ratchet needs to get the attention of the entire room and goes WEEWOOWEEWOOWEEWOO