help 2.5 tdi ake

i have a 2002 audi allroad 2.5 tdi ake i bought it as a none runner got it running now but on the drivers side head just in front of the exhaust manifold there is a machined hole if you look into it you can see the exhaust valves and when its running exhaust gases are coming out does anyone now what should go in there thanks james

Sounds like a pipe for the EGR circuit is missing. Just a wild, uneducated guess on my part.