Can a bad EGR valve cause a P0171 code?
IT COULD ALSO BE: A BAD DPFE SENSOR Ford p0171 AND p0174 lean codes can also be set by a bad EGR differential pressure sensor. These sensors have a very high failure rate once a vehicle has more than about 60,000 miles on the odometer or is more than five or six years old.
What does code 174 mean?
Code P0174 indicates that there is a lean condition detected by the Engine Control Module (ECM). A lean condition will be created if there is too much air, and not enough fuel, in the air fuel ratio (AFR).
Can a bad EGR cause a lean code?
Unwanted EGR flow at idle, even in very small amounts, causes a type of rough running that may easily be misidentified as a lean condition (somewhat more likely in MAP-based fuel systems).
What causes a lean mixture on the p0171 code?
Intake leaks are a widespread problem when it comes to the P0171 code. Intake/Vacuum/boost pipe leaks can trick the MAF sensor and cause a lean mixture. The MAF sensor measures all air that is going into the engine and telling the engine control unit which amount of air it is.
What causes a lean mixture code to be triggered?
Step 2 – Un-metered air which enters the intake system of the engine can cause a lean mixture code to be triggered, inspect all vacuum lines for cracks or dilapidation. Check the integrity of vacuum hoses at each end of the hose.
Where do I find the lean fault code on my car?
So your car’s CEL (always check Engine Light) is on and also you had the codes scanned at a local parts shop. (Or maybe used your own OBD scanner to extract the car faults). Your car or truck has either a P0171, P0174 lean fault code or both stored in the pc, these codes derive from Oxygen Sensor (O-2) readings.
Why does my engine have a lean code?
This will cause the exhaust system to test lean as tested by the O2 sensors, this can sometimes be fixed by a tune up . Step 8 – An air intake boot transfers engine air from the mass air flow sensor to the throttle actuator. If the boot fails, it can cause a false reading from the mass air flow sensor producing the code.