| 摘要 |
The invention is directed to a method for checking the tightness of a tank system of an internal combustion engine having an intake pipe. The tank system includes: a fuel tank wherein fuel vapor forms, a regeneration valve connected to the intake pipe; an adsorption filter connected between the regeneration valve and the fuel tank; the regeneration valve being movable between a closed position and an open position wherein the fuel vapor is drawn by suction into the intake pipe; the adsorption filter having a venting line; and, a shutoff valve for the venting line and being movable between a first position wherein the venting line is closed off pressure tight and a second position wherein the venting line is open to the adsorption filter; and, a pump for generating a diagnostic overpressure in the tank system. The method includes the steps of: generating a diagnostic overpressure in the tank system with the regeneration valve in the closed position and the shutoff valve in the first position; first moving the regeneration valve to the open position; measuring the pressure in the tank system; and, then switching the shutoff valve into the second position when the pressure in the tank system corresponds essentially to atmospheric pressure. |
