i have a bolt ons 991 turbo s and I'm having problems with misfiring and maybe you guys might help, so my car had the Techart piggyback and everything was fine till I changed my spark plugs and drove it for 500km so I decided to have COBB installed. Before removing the Techart piggyback, I went to the Dyno to see how much hp does the car make on Techart before removing it so after having the first Dyno pull I realized that there was misfiring on high RPMs, so I removed it and installed Cobb tuning to make sure if it's a mechanical issue and still the misfiring is there so basically it's an mechanical issue, as the tuner said there is a small boost leak on bank one but I really don't know could it be that one of the coils are damaged ? Or is it from the boost leak ? Vacuum hoses and spark plugs are checked and nothing seems to be wrong .. One of my friend suggested that it might be leaking from the intake manifold and others said coils might be damaged .. So what do you guys think of what's causing the misfiring ?