Can a bad PCV valve cause a P0171 code?
The most common causes of the P0171 code are vacuum or intake leaks, low fuel pressure, faulty PCV valve, or a faulty MAF sensor. Other things can also cause the P0171 code.
Can a bad O2 sensor cause a P0171?
Additional Causes of Code P0171 A plugged Fuel Filter or poorly functioning Fuel Pump can set the P0171 code. The computer hears (accurately) from the Oxygen Sensor that the Fuel Mixture is too lean so the computer keeps increasing the amount of fuel being delivered into the combustion chambers.
What does the p0171 code in front oxygen sensor mean?
If the P0171 is combined with the P0174 code, it’s very likely that the problem is caused by an intake leak. If there are no intake leaks, the next step is to replace the air filter and clean the air flow meter. If the problem persists the front oxygen (O2) sensor may need to be replaced.
What does p0171 mean on a fuel mixture?
If it’s a short-term lean mixture the fuel mixture is often very lean. If it’s a long-term mixture, it can register the code because of a small notice of lean mixture over time. The P0171 code means that the front O2 sensors have recognized a lean mixture. The front O2 sensors are adjusting the fuel mixture that is coming out from the engine.
What are the symptoms of a p0171 leak?
What Is The Cause Of P0171? 1 Dirty or faulty mass airflow sensor 2 Vacuum leaks – PCV hoses, vacuum hoses, intake manifold gasket. 3 Weak fuel pump 4 Clogged or dirty fuel injectors 5 Clogged fuel filter 6 Exhaust leak 7 Faulty oxygen sensor 8 Faulty air-fuel ratio sensor
What causes a p0171 code on a PCV valve?
Here are the most common fixes to the P0171 code. Most common from the top. A common diagnostic mistake is to start replacing parts without making a proper diagnosis. In most cases, the P0171 code is caused by something easy as a vacuum leak or a bad PCV valve.