Your check engine light is on, and you got the code P0171 or P0174, "system too lean." That means your vehicle's engine does not have enough fuel for the amount of air it is getting; a lean mixture. An engine running lean can have a negative impact on performance, and can cause damage! In this video, Andy walks you through the steps of diagnosing and resolving the different problems that could cause this code, from the simple: a loose intake fitting or hose; to the more complex: a faulty fuel in

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