While changing my plugs and wires this weekend, I noticed this hole in the inlet manifold. Should there be a bolt in there? If so, anybody know the length/size?

It's clear somebody with "questionable attention to detail" has poked around the engine compartment before, so I get nervous when I see things like this.

 

Drain hole? I don't remember anything being there when I took mine apart. I think you're okay.

 

Will your rig is tasty dude... shwing!!!

That hole is where the gizmo adapter goes... I think its in relation to the thingamabob but Im not sure.

 

I don't believe that is a factory hole and once verified, I would plug it.

 

Ugh, I don't like the sound of that. If it was added, I wonder what the original goal was...(lazy inspection hole?)

I haven't had things far enough apart to know what is directly under it. Anything on the other side to worry about?

 

It's a drain hole for water (not coolant, think water crossings). It doesn't go inside the intake, that's just a support webbing. You can plug it or not, doesn't really matter unless you get water in there. (then it still probably doesn't matter, the heat these engines put out would evaporate any trapped water in short order)

 

Of the three Bosch engines I own, one has this hole. There is a plate type gasket below, sealing the upper and lower manifolds. Water flowing in from a wash will drain to the gasket, then out the back if there is sufficient space, without harm. I'm only guessing, but I think the hole may have been used in some way to suspend the gasket during assembly, with the fastener removed once the upper manifold was in place.

 

Thanks everybody. Sounds like the consensus is it's a standard feature that an engine may or may not have. Guess I won't worry about it.