Got a used d16z6 head about a year ago, just now got around to breaking it down for rebuild. Yesterday I discovered there is a chunk missing from the roof of the #4 exhaust port, the left port, looking at the exhaust side. Looking in from the header side, it is just past the valve guide, but doesn't go into the valve guide area. It is slightly smaller diameter than a dime. It is fairly deep, but doesn't look to go through to the coolant passage. Seems as though it's been there for awhile, due to the carbon buildup in it. I don't see any signs of a dropped valve or anything obviously disasterous causing this.

Has anyone ever seen anything similar to this before? Should I make a new boat anchor from this one or is there any chance to repair. I suppose it could be filled by a weldor and reshaped, but I'm not if that would be worth it. I'll try to post pics later. Any suggestions? JB Weld FTW??

 

I think what you are seeing was the remnants of an EGR that never made it into production--its just a hole that doesn't lead anywhere. My a6 has that same hole in the #4 exhaust port.

 

hellz yeah on the jb weld.

nah for real i would get yourself another head. you could probably find one cheaper then you can get that one fixed for.

 

hmm, I've got an a6 head laying around. I'll have a look at it tonight...

I've also noticed on this head that on one of the oil drains, it doesn't look like it was machined through all the way, like it's only 1/2 open. Is that normal?