Fuel vapor leakage detection method for motor vehicle fuel tank or fuel vapor purging system involves suspending leakage detection when vehicle rapidly descends slope to avoid false detection due to increasing atmospheric pressure

摘要

The fuel vapor leakage detection method involves determining the leakage in the fuel tank or fuel purging circuit as a function of the rate of pressure variation in the circuit (413). The method involves a first stage for detecting the slope grade of the road on which the vehicle is travelling and a second stage for preventing leakage detection when the vehicle is determined to be travelling along a downwards slope, to avoid errors in the detection of fuel leakage due to atmospheric pressure changes.