ECU temperature sensor failure
Car failure phenomenon for the idle shaking, Since there is no fault code, Can not determine the location of the fault.
According to the fault phenomenon, The possible mechanical failure has been checked, R uled out the throttle carbon deposition, And idling control actuator block and other causes of failure. There may be electronic control system is faulty, But the self-diagnostic system can not be monitored.
According to this analysis, the fuel pressure was first tested. From the results, the fuel system is normal. And then use AUTOBOSS computer diagnostic apparatus to check the electronic control system. When the throttle valve is slowly opened from the idle position to the fully open position, Inhalation of air and fuel injection time with the throttle open large and uniform increase, all normal.
Step on the accelerator pedal,S o that the engine speed increases, the load increases, Observe the coolant temperature rise,Found that the temperature did not rise evenly. The data of the intake air amount is normal, But the throttle opening angle data values have changed abnormally. From the idle position to open to about 45 ° range, Data value increase rapidly; In the range of 50 ° ~ 70 ° data values increased slowly, That is, the change of the data value lags behind the actual opening angle of the throttle valve.
It can be judged, As the throttle position sensor operating characteristics have changed, the sensitivity decreased, The rapid opening of the throttle unresponsive, ECU issued the wrong instruction. So that the injector can not quickly respond to changes in throttle opening, Fuel injection lag, Resulting in slow engine speed increase, Poor acceleration.
Replace the throttle position sensor, The road test, the phenomenon disappeared!
According to the fault phenomenon, The possible mechanical failure has been checked, R uled out the throttle carbon deposition, And idling control actuator block and other causes of failure. There may be electronic control system is faulty, But the self-diagnostic system can not be monitored.
According to this analysis, the fuel pressure was first tested. From the results, the fuel system is normal. And then use AUTOBOSS computer diagnostic apparatus to check the electronic control system. When the throttle valve is slowly opened from the idle position to the fully open position, Inhalation of air and fuel injection time with the throttle open large and uniform increase, all normal.
Step on the accelerator pedal,S o that the engine speed increases, the load increases, Observe the coolant temperature rise,Found that the temperature did not rise evenly. The data of the intake air amount is normal, But the throttle opening angle data values have changed abnormally. From the idle position to open to about 45 ° range, Data value increase rapidly; In the range of 50 ° ~ 70 ° data values increased slowly, That is, the change of the data value lags behind the actual opening angle of the throttle valve.
It can be judged, As the throttle position sensor operating characteristics have changed, the sensitivity decreased, The rapid opening of the throttle unresponsive, ECU issued the wrong instruction. So that the injector can not quickly respond to changes in throttle opening, Fuel injection lag, Resulting in slow engine speed increase, Poor acceleration.
Replace the throttle position sensor, The road test, the phenomenon disappeared!
