PC-85-928S

1989 S4
Air pump gone-diverter going-
I want to cap the cat at the threaded part of the air injection tube.
anyone know the size?
(I searched-could not find)

davek9

If you still have the Testing Tubes that ran up topside by the Intake, you can use the same fitting, cut it off the tube (most tubes are rusted and broken).
. Then place a small ball or a small round head screw in that threaded end to act as a plug and reinstall it.
Porsche did actually sell a cap, but not cheep IIRC.
Sorry don't know that thread size

Ramp

I used a copper end cap with some JB Weld as a sealant. Fit nicely and does not permanently damage the tube. I think it was 3/4"

Taguid

I just used the JB weld putty 2 days ago but haven't reinstalled to see if it holds but I think it will.

Kevin in Atlanta

This is the bomb for this kind fix. Tear off a piece, knead it and push it into place.

PorKen

M22 x 1.5

DIY captured 3/4" ball bearing

Taguid

\
That is exactly what I used.

Rob Edwards

Porsche makes a plug for that, 928 113 216 00- Absurdly expensive for what it is....

skpyle

And this is surprising how...?

gearz

Gates makes a cap for this that is plug and play. Part# G64793-0015
Looks good too!
https://www.gates.com/us/en/fluid-po...00842/v/391710

PorKen

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