Function Explanation (DTC Detection Outline)
- The PCM detects the oxygen concentration in the exhaust gas from the A/F sensor signal and performs fuel injection amount feedback to maintain the optimum air/fuel ratio. If a condition in which the feedback correction amount is small (fuel injection amount being decreased) continues for the specified time, a feedback correction amount malfunction is determined, and a DTC is stored. The feedback correction amount has a "Fuel feedback correction amount" for the air/fuel ratio and a "Fuel learning correction amount" for fuel injector deterioration over time.
- "Fuel feedback correction amount (SHRTFT1)" and "Fuel learning correction amount (LONGFT1)" can be verified from the M-MDS PID item.
- The sum of the fuel feedback correction amount (SHRTFT1) and the fuel learning correction amount (LONGFT1) is the specified value (-25 %) or less, and 10 s or more have elapsed with the fuel learning correction amount (LONGFT1) at the specified value (-15 %) or less. Engine coolant temperature: 0-45 °C {32-113 °F}, 60 °C {140 °F} or more
Courtesy of MAZDA MOTORS CORP.
- Fuel learning correction amount (LONGFT1) at the specified value (-25%) or less. Engine coolant temperature: 0-45 °C {32-113 °F}, 60 °C {140 °F} or more
Courtesy of MAZDA MOTORS CORP.