Fuel Tank Pressure

The scan tool displays -32.7 to +14.0 mmHg (-17.5 to +7.5 inch H2O). Fuel Tank Pressure is used extensively for EVAP purge control and EVAP system diagnostics.

The scan tool displays 0 to 5 volts. Fuel Tank Pressure is used extensively for EVAP purge control and EVAP system diagnostics. Fuel Trim Cell: The scan tool range is 0-9. The fuel trim cell is dependent upon the engine speed and the MAF sensor readings. A plot of RPM vs. MAF is divided into 10 cells. The fuel trim cell indicates which cell is currently active.