Hey Maby some one can point me in the rite direction before I get killed at the dealer , I just changed my plugs on my B9 sq5 car was misfiring no check engine light , changed the plugs ,stock plugs from audi. The dealer said they was pre-gapped. So I changed them out everything back together all connectors and wires are in good connection, engine light now goes on after first start up super rough idle . Scanned car says cyl 1 missfire. The car runs fine tho after heating up and driving normal under boost checked connectors when the car warms up it seems to idle ok. on cold starts the miss-fire is super bad. But as the car heats up it seems ok. Also swapped coil and rechecked the codes and no change.. Update now I think car has a boost leak possibly car runs and drives absolutely fine a tad slow car is stock to my knowledge , although it Deff feels like a boost leak , weird y thr cel is on for cyl one missfire shouldn’t I get Missfires across more cylinders as well. If anyone has any ideas I appreciate it. Maby a common boost leak spot to check idk thank you