05 Equinox bucking maybe missing

[Deshooter]

Hello. I've been experiencing hesitation , bucking, maybe missing when power is needed say for a hill or overtake a lane etc. Is there a sensor on the Trans maybe an overdrive? An ignition system problem?There was a new code p0300 but all these symptoms were before code and now after replacing coil pack there's improvement but still doing the same thing on certain hills and when I press for extra power on highway. I have to press it slowly and let it build speed if that makes any sense. I have one code p0420 been there since I can remember and car has never acted this way. Any insight would be greatly appreciated thank you

 

[cavell]

How old are plugs and wires? 20 yr old car.

 

[Big Papi]

Random misfire and a long standing cat code, 20 year old car, poor acceleration. Could be almost anything but that combo would have me testing for a plugged cat for starters. Good luck. Take out the B1S1 0² and take 'er for a rip. Run better?

 

[Deshooter]

How old are plugs and wires? 20 yr old car.

New plugs,wires, coil pack, map sensor