| 摘要 |
Fuel injection is switched off during a test interval or the fuel air ratio is altered. Reaction times (t1, t2) are measured, up to appearance of the resultant signal variation (rapid response) from the O2 sensors (3, 6). The difference ( DELTA t) is formed. This enables sensor (3, 6) exchange to be recognized, when the difference undershoots a threshold or is negative. An Independent claim is included for an engine equipped to make the test. Preferred Features: In a similar variant method, reaction times are compared with a given reaction time window; it is then ascertained whether the result lies outside the window. The time to signal variation, is determined by comparison with a given signal threshold value. On detection of an exchanged sensor, an error signal is produced and/or the controller (9) is blocked. The error signal is sent to an engine management unit or to an external test unit connected to the engine. |
