What is the lean code for an OBD 2 engine?
The OBD II system may or may not detect the fault and set a lean code (P0171 and/or P0174) in addition to misfire codes. Unmetered air that gets into the engine behind an airflow sensor can lean out the fuel mixture to the point where it may not ignite when the spark plug fires.
When do you know you have a lean code?
Step 1 – Once a check engine or service engine soon light has determined a lean engine code has materialized, a repair procedure inspection is needed. Explanation: A lean code is enabled when the computer has detected enrichment adjustments have maxed out, with no results, this inability triggers the lean code.
How to fix automotive engine lean exhaust codes?
Begin with the vehicle parked on flat ground in park with the emergency brake set. Step 1 – Once a check engine or service engine soon light has determined a lean engine code has materialized, a repair procedure inspection is needed.
What does it mean when your engine is too lean?
System Too Lean (Bank 1) What the P0171 code means The P0171 OBD-II code means that, on the first bank of the engine, the fuel system is running weak or a vacuum leak exists near this side of the engine. A lean condition occurs when the engine either receives too little fuel or too much air.
Step 1 – Once a check engine or service engine soon light has determined a lean engine code has materialized, a repair procedure inspection is needed. Explanation: A lean code is enabled when the computer has detected enrichment adjustments have maxed out, with no results, this inability triggers the lean code.
Begin with the vehicle parked on flat ground in park with the emergency brake set. Step 1 – Once a check engine or service engine soon light has determined a lean engine code has materialized, a repair procedure inspection is needed.
How does a PCM diagnose a lean running engine?
Lookup tables in the PCM retrieve a base injector on-time command. This base command is then modified as needed based on inputs such as engine speed, barometric pressure, engine coolant temperature and TPS and its rate of change. The result becomes the injector pulse width command, which is then fed forward to the injector.