P0171 – Meaning, Causes, Symptoms, & Fixes
Code P0171 Definition Bank 1 has too much air or not enough fuel. What Does P0171 Mean? Combustion engines run most efficiently when they maintain an air-fuel mixture ratio of 14.7 parts air to 1 part fuel. When there are more than 14.7 parts air to 1 part fuel in the air-fuel mixture, a lean...