Have just replaced a worn camshaft & lifters in my 2008 Skoda Octavia Scout 2.0 TDI Engine type BMM.

Engine starts and runs OK but there is a new tapping noise.
Holding my ear to screwdriver that is touching engine head, it seems to be stronger on the No4 cylinder end (fuel pump end).

Oil is also leaking from valve cover at this end of motor.
If I unscrew oil filler cap while motor is running there appears to be a lot of are pressure in the valve cover.

Is the valve cover pressure normal?
Looking for suggestions on checks to do to help isolate the problem?

Thanks