chall

2010 HHR has developed a miss it has the 2.2 ,I have replaced all of the coils and plugs and the MAF ,COMPUTER SAYS MISS #2 CYLINDER .the car is running worse than before ,at a loss ?

Oldblue

First off , welcome to the site, second thing is , stop throwing parts and money at it, let’s analyze the problem.

I’m understanding your OBD II port is giving your code reader code P0302,
if you still have your original MAF sensor put it back into position.
What brand coils did you install, and the parts numbers?
if you still have the original coils marked for their original cylinder, put them back on the engine.
do you have the Oriya park plugs, did you mark them , which cylinder they came from ?
if you do, post pictures of them here so we can see what the problem is.

Did you install AC Delco 41-103 Iridium spark plugs?

how old and dirty is your air filter?
have you had any engine work done lately?

any evidence of rodent activity under the air filter box? They love snacking on wiring harness.

please get back with some answers and we’ll go from there.

sleeper

Welcome aboard.