i recently wrecked my 01 s2 and bought a replacement that had an engine swap (MY02, 130k miles, leakdown tested compression is good). it had a knock sensor code and misfire so i got that swapped out, but it's still showing a misfire code for all 4 cylinders. engine runs strong and i dont feel or hear any misfiring. any clues as to what might be the issue? spark plugs were replaced yesterday, valve adjustment today.

i just want to be on the road again without fear of catastrophic engine failure. any help will be much appreciated. i have a very capable friend doing the work, just need to diagnose what the issue is.