Air pump?

[Schurkey]

My '88 K1500 5.7L has an AIR pump. No idea why, unless it was originally sold in an area the EPA figures is overly-dirty.

 

[PlayingWithTBI]

I'm curious what trucks even had them. I've always wondered what the empty spot was on my accessory bracket, and of the several junk yard trucks I've pulled parts from I'd never seen one of these pumps in person

Come to CA, you'll see them in just about every truck until they came up with 3 stage CATs and better controls. FWIU Federal Emissions didn't require them, CA and some other states that adopted/modified it from CA.

 

[Majoraslayer]

I'm in TN, so I'd say a lot of them around here just straight up got deleted as well.