Internal combustion engine controller diagnosing method for motor vehicle, involves performing on-board diagnosis for checking adaptation of engine controller to composition of fuel mixture by testing device

摘要

The method involves determining portions e.g. alcoholic portions, of fuel of a fuel mixture (20) in on-board under consideration of temperature by an alcohol-sensitive sensor (13) in a testing device. A motor controller is adapted to compositions of the fuel mixture. An on-board diagnosis is performed for verification of adaptation of the engine controller to the composition of the fuel mixture by the testing device. The on-board diagnosis is verified by off-board testing such that a value determined the off-board diagnosis is compared with a value determined by the on-board diagnosis. An independent claim is also included for a device for performing a diagnosing method, comprising a testing device.