DTC P0171: Fuel Trim Too Lean: Condition

DTC is set when fuel injection closed loop correction and learning correction are greater than specified value because of system too lean. Deterioration or malfunction of following components and/or systems could contribute to DTC P0171 being set. Possible causes are:

• Fuel injector malfunction.
• Fuel pump malfunction.
• Fuel filter clogged.
• Fuel lines clogged or leaking.
• Pressure regulator malfunction.
• Pulsation damper malfunction.
• Ignition coil malfunction.
• Ignition module malfunction.
• Ignition wire malfunction.
• Spark plug malfunction.
• Intake air system leakage.
• Exhaust system leak.
• Low compression.
• Front oxygen sensor malfunction.
• Wiring or connector malfunction.
• Vacuum hose leak.