Vacuum Leak at Smog/AIR pump

[Papikev252]

1998 K3500 7.4L in California.

I had been chasing a vacuum leak for a while. Bought a smoke leak detector and I saw a big cloud of smoke coming from behind the smog pump. Is the pump bad? Is there a seal or hose on it I can replace to where it may be leaking? I just want to see what to look for when I get to taking it off to inspect. I’ve seen people say delete it and it’s fine and I’ve also seen some say it’s better with it.

Best video I could get:

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[Crussell45]

I’m following this. I eventually want to delete the smog and egr junk.

 

[Schurkey]

1998 K3500 7.4L in California.

I had been chasing a vacuum leak for a while. Bought a smoke leak detector and I saw a big cloud of smoke coming from behind the smog pump.

WHERE are you injecting the smoke?

Wild Guess: Into the intake manifold, perhaps via a throttle-body vacuum port.

In which case, the smoke is probably coming up the throttle body, into the air cleaner, and then backwards to the AIR pump via the diverter hose.

If that's the case, the smoke at the AIR pump means nothing.

I’ve seen people say delete it and it’s fine

I’m following this. I eventually want to delete the smog and egr junk.

That's insane.