Hola guys. Friday my 01 TT came back from the body shop, with a fresh respray on pretty much the whole car (outside looked brand spanking new), and by Saturday it was sold!! I didn't even get a chance to tell anyone I was selling it!

Anyways back to my 02 TT. At Waterfest I had a coilpack fail. Luckily 034 Motorsports was in the booth across from us and they had coilpacks for sale. They also had bosch super spark plugs 3 electrode (F6DTC) so I grabbed a set. Changed out the bad coilpack and went on my way (without changing the plugs). Car ran fine for a week, at which point I started getting misfires again in the same cylinder. So this time I checked the coilpack - it was fine, and went to change the plugs to the bosch supers I bought before. There is no gapping on these plugs since they are 3 electrode pre-gapped. Now I have a smooth running car but am not boosting over 16-17 psi (normal is 23psi).

What could be causing this?

 

Which packs are you using? You could be in soft limp and the plug could be backing out, might want to check the tq on it. Another issue could be a bad wire to the pack causing occasional missfires

 

3 are hitachi, 1 is from 034 motorsports (not hitachi).

No misfires, monitored with vag.