Honda P0171 Fuel System Too Lean Too Much Oxygen Or Too Little Fuel In Exhaust System
Code P0171 Honda is DTC code indicates that engine is running too lean which means that there is too much air and not enough fuel in the air-fuel mixture.
Possible Causes Code P0171 Honda
1.Unmetered air entering engine through vacuum leak causing air-fuel mixture to become lean. Most common source of vacuum leaks involve damaged hoses, damaged hoses clumps or damaged intake manifold gasket.
2.MAF sensor measures the amount of air entering the engine and pass on this information to ECM. If mass airflow sensor is damaged, dirty or not functioning correctly it may send wrong information to engine control module resulting lean air-fuel mixture.
3.Oxygen sensor measures the amount of oxygen present in exhaust system and send this information to engine control module. If oxygen sensor is damaged, clogged or is not functioning correctly it may send incorrect information to engine control module resulting lean air-fuel mixture.
4.Choke fuel injector or fuel filter may restrict free flow of fuel to the engine resulting lean air-fuel mixture.
5.Low fuel pressure may not provide enough fuel to the engine resulting lean air-fuel mixture. Common cause for low fuel pressure include faulty fuel pump, choke fuel filter or faulty fuel pressure regulator.
6.Exhaust leak can cause the air-fuel mixture to become too lean.
7.Fuel pressure regulator not functioning correctly may allow too much fuel resulting air-fuel mixture to become too lean.
Honda P0171 Possible Symptoms
1.Too lean running may stall or may have rough idle.
2.Lean air-fuel mixture may cause engine to run poor resulting in reduction of power or slow acceleration.
3.Engine may hesitate or stumble during acceleration.
4.Lean air-fuel mixture can cause increased emissions resulting in failed emissions test.
5.Lean running engine may consume more fuel resulting in poor fuel economy.
6.Check engine light illuminates on dashboard.
7.In extreme condition p0171 can cause drivability related issue such as engine misfiring, engine stalling or lack of power.
How To Fix P0171 Honda
1.Inspect vacuum hoses, connection and gasket leaks replace or repair damaged components.
2.Inspect mass airflow (MAF) sensor if MAF sensor is dirty or choke it may not provide accurate information to ECM resulting lean air-fuel mixture. Clean MAF sensor or replace it if necessary.
3.Damaged or choke O2 sensor may not provide accurate information to ECM resulting lean air-fuel mixture. Clean O2 sensor or replace it if necessary.
4.Inspect fuel pressure to ensure that it is within manufacturer specification. If fuel pressure is too low replace fuel filter or fuel pump.
5.Dirty or clogged fuel injector may not provide enough fuel to engine resulting lean air-fuel mixture clean or replace fuel injectors if found faulty.
6.Exhaust leaks can allow unmetered air to enter engine resulting lean air-fuel mixture check for exhaust leaks and repair them.
Its important to have the vehicle inspected and diagnosed by professional mechanic to find and resolve issue related with p0171 for proper repair.