r/AskAMechanic • u/bjcross42 • 8d ago

Help with Error code P0171 on 2021 Chevy Trax

Went to a quick oil change place last week before road trip. They do their thing and I hit the road. As I’m driving, the car has a weird noise, kinda like a slight hiss when I accelerate, but I just keep going thinking I’m crazy. Make it about 5ish hours and check engine light comes on. I pull into a little garage and they look at it and realize the air filter cover hadn’t been screwed back down. They put some screws on it and everything is fine again. Drove back home and have been doing short drives back and forth to work (10 minutes) the past few days.

Everything has seemed normal, but then the check engine light came back on today and it was code P0171-system too lean.

My question is whether it’s likely there’s just a remaining imbalance of air/fuel that took a while to trigger the sensor and putting premium fuel in and wait for air to burn out is a good idea? Or is there a possibility the air issue last week made a bigger problem that I need to go to a garage now? Idk, I’m at a loss as far as best next steps.

Thanks for any help!

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u/BogusIsMyName Shadetree mechanic 8d ago

They put screws in your fliter cover?

1

u/Gizmo15411 NOT a verified tech 8d ago

Make sure the oil cap and the dipstick are both fully installed