Left a little gas in the tank for ya

Meaning

A considerate way to say you did not finish the last bit of a communal item, like the coffee pot or the milk carton. It is a humble brag about your own restraint.

Polite, considerate

Used in a sentence

• I finished most of the coffee but left a little gas in the tank for ya.
• Check the milk carton, I left a little gas in the tank for ya.
• I did not eat the last donut, I left a little gas in the tank for ya.