Green’s Dictionary of Slang

suck wind v.

1. [1960s+] (US) to be on one’s last legs, to be struggling.

2. [1960s–70s] (US teen) a dismissive retort to someone who is showing off.

3. [1970s] to show off, to boast emptily.

In phrases

have one’s face out a yard and sucking wind (v.) [one fig. gasps for air]

[1970s] (US) to be a braggart.