Originally Posted by kk3an
I also had a very pronounced detonation / pre-detonation issue caused by throttle blips with my '13 GSA.
Removed the exhaust flap and the problem went away 100%. No throttle body sync, no nothing - just replaced the exhaust flap with a straight section of pipe and the issue was gone.
I'm about to do the flap delete. However, I'm wondering if you had any fault code issues when you did yours?