What is the diagnostic code for small leak?
What is the diagnostic code for small leak? P0456 is a diagnostic trouble code (DTC) for "Evaporative Emissions System Small Leak Detected". What is the trouble code for the EVAP system? Trouble Code: P0456 Evaporative Emissions System – Small Leak Detected. The EVAP system is a closed system that captures fuel tank vapors and prevents them from escaping into the atmosphere. What causes the ECM to turn on the Check Engine light? If the system detects a very small leak during the test then the ECM stores the code and waits till a second test can be done and if...