Patent ID: 6615808
Filing Date: 2003-09-09
Classification: F02M

Abstract:
A method for checking the tightness of a tank system of a vehicle, the method comprising the steps of:introducing an overpressure relative to the atmospheric pressure over a pregiven time interval utilizing a pressure source alternately into the tank system and a reference leak of a defined size connected in parallel to the tank system; detecting at least one operating characteristic variable of said pressure source when introducing the pressure into the tank system to provide a tank measurement as well as when introducing an overpressure into said reference leak to provide a reference measurement; comparing the tank measurement to the reference measurement; when there is a deviation of the tank measurement from the reference measurement by a pregiven value, drawing a conclusion as to a leak; when a conclusion as to a leak is drawn, introducing pressure into the tank system over a further time interval and lengthening said tank measurement; thereafter, executing a renewed reference measurement; and, outputting a fault announcement â€œleakâ€  only when, by the latest, after the elapse of said further time interval, the tank measurement deviates from the renewed reference measurement likewise by a pregivable value.