If that don't get your knock sorted out, you might check what size injector seals were used. IF they are to big OD, they will not fit down into the pocket
inside the injector hole.
This causes the tip of the nozzle to sit to high, and part of the spray pattern will hit the head, causing a pinging/rattleing noise.
I had this happen to mine when installing injectors. Get the OEM ones, as there have been several people who early on bought injector install kits
that got the wrong ones. I think it has since been sorted out, but it is good to check on it.
There is a thread on TDIclub.com that actually shows the nozzle in a head that was removed from the engine, and it is sitting to high in the head.
They show the difference with a correct washer too..
Made my car sound a lot smoother, and a lot less smokey with the same
ECU parameters. Now I can tweek the IQ setting up a bit more for just a
touch of smoke on WOT!
or run this way and get better MPGs!
Drive ON!
Arnie