| 摘要 |
Oxygen sensor deterioration is detected by initially counting the number of fuel units required to change the output voltage of a nondeteriorated sensor between first and second voltages, and subsequently counting the number of fuel units required to change the output voltage of the sensor between the first and second voltages, as the sensor ages, until a subsequent count exceeds the initial count by a given amount. The method detects when the air/fuel ratio desired for normal engine operation drifts outside acceptable tolerance. The method detects and stores a first difference between air/fuel ratios, corresponding to first and second sensor output voltages, and then subsequently detects a second difference between air/fuel ratios, corresponding respectively to the first and second sensor output voltages. When the second difference exceeds the first difference by a given amount, deterioration is indicated. |
