Please Help With This Mystery Problem 2015 Cruze 1.8

Hi,

I hope someone out there can help me, I purchased a 2015 Chevy Cruze LS 1.8 about a month ago. All was good until about 2 weeks ago, the car starts up and runs great, but that's when the big Mystery Problem started. OK I can drive the car all day long on the interstate, but when I come to a stop sign or red light, the car will start acting up. It'll have a rough idle and sometimes stops running, but it'll start right back up.

The Check Engine light came on and it showed 3 codes, P2270, PO171 and a PO131. I watched a few videos, so I decided to smoke the engine and smoke came out from around the valve cover. I got a new one and installed it and I also put 4 new AC Delco plugs in. I then cleared the codes and drove it around for about an hour with no problems and no light, Well I thought it was done.

My wife works for Door Dash and took it out the next morning and about an hour later she calls me and says the light is back on and so is the rough idle, she said it quit on her once at a red light. She brought it home and the same codes are back. I don't another smoke test and didn't see anything. The car does great the only time it acts up is when we have to stop.

Well what do you think could be the Mystery Problem? This is the only car we have right now and her door dashing is the only income we have right now cause I got laid off and the company I worked for is fighting my unemployment.

I'll be watching for you're reply and thank you in advance.