Circuit Description

PCM uses fuel level input in order to calculate expected vapor pressure within the fuel system. Vapor pressure vary as fuel level changes. Vapor pressure is critical in determining if EVAP system is operating properly. PCM also uses fuel level to determine is fuel system is too high or too low to be able to accurately detect EVAP system faults.

DTC will set when fuel level input has not changed more than 1.6 percent in 120 miles.