It's a PEP talk he made
when he was a kid.
The Big Bang Theory Season 12, Episode 10
And if you think
some PEP talk can fix that,
The Big Bang Theory Season 12, Episode 9
Okay, thanks for the PEP talk.
The Big Bang Theory Season 8, Episode 3
The man down at Pep Boys
says from now on,
The Big Bang Theory Season 5, Episode 21
Based on this PEP talk,
I'd say you're still doing it.
The Big Bang Theory Season 9, Episode 17