My Chevy I have had for not even a year won't stop misfiring in the third cylinder. I have gotten spark plugs new fuel filter a new air filter and a new coil pack in the last 2 months it's nonstop nobody knows what it is and the fuel injectors were tested too. I'm out of resources please help

 

perform a compression test of all cylinders

 

Ok I will have my mechanic do that

 

It was actually the power source to the coil pack that silver peice on the top it was never changed when got new coil pack