my exhaust was leaking around the air tube and won't tighten up. So I am pulling the tubes out and plan on just plugging the hole in the manifolds. I know they are not normal pipe thread or gas or flare fitting sizes. I am thinking they are a straight m22 x 1.0 or so. Anyone confirm/deny this or know of a source (like a hardware/homeimprovement store) that might have what I need? I don't care if it's ugly for right now, so even a bolt will work if I can find the right thread.
Suggestions?

 

Napa has the plugs they are size M22 drain plugs. Napa part#704-1048. Removing AIR system will really remove some of the clutter from the engine bay. They are about $8 a piece.

 

I found an $0.02 solution
I pulled the fittings, cut off the tubes and removed them, then I cleaned out the threads and seats in the manifolds. I got some JB weld, spread it around the edges and stuck a penny into the goo. Then I put a little more on top and screwed the fittings back in. Sealed it right up

 

After asking at our NAPA store, the guy had no clue, even though I gave him the NAPA number. I found a much easier solution. Go to your local Jiffy Lube and ask for an M22 1.5 Drain plug. They fit Toyota transfer cases and differentials.

I called all over for these until a national distributor told me that they only sell to 10 min oil change places. He asked if I had a Jiffy Lube and suggested I call them. When I did, they had eight in stock for either $3.99 or $4.99 (I can't remember). They fit perfectly and even came with a sealing ring. Problem solved.