Misfire #2 and exhaust backfire through intake PLEASE HELP?

Question

I have a 2006 chevy impala lt. recently it started to bog down and drive horable. it eventually gave me a multi cylindar misfire code so i changed all sparkplugs and ignition coil. Also thee cat. but same thing i dont undrstand why its still doing it. it start perfect but when you smash on the gas a loud pop comes from the air filter and the car struggles to rev up. idles normally from what i can tell any ideas???

Answer 1

This type of engine this has a MAF (mass air flow) and a MAP (manifold absolute pressure) sensor, If it idles good but does not accelerate, the MAP sensor that is faulty can do this.