1988 GMC Sierra Air injection?

[Supercharged111]

I found that thread at Lowe's believe it or not, assuming the Vortec EGR tube uses the same kind of thread and tapered sealing end.

 

[PlayingWithTBI]

I did a little research and a guy on GMSquarebody.com found one that will plug the hole, it's M22-1.5 thread, he used an oil pan drain plug, ha ha.

https://www.autozone.com/external-e...-engine-oil-drain-plug-652886/257234_959501_0

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