What are lean codes: P0171 and P0174 indicate a lean fuel mixture on Bank 1 and Bank 2, often detected by upstream oxygen sensors. Why they matter: Lean conditions can cause misfires, hesitation, ...

Your check engine light isn’t just an annoying glow—it’s your car’s way of telling you something’s wrong. From loose gas caps to serious engine misfires, understanding the codes behind the light can ...