Involved models: Honda Civic, mileage 167820km.
    Failure phenomenon: the impact of large block, into the D block when the impact of a large, in the process of driving 4 block down 3 block when the impact is obvious.
    Troubleshooting: the gear switch adjustment is invalid, repair the transmission assembly, the fault still exists.
    Failure analysis: This car hot car hanging N block, the engine speed is low, only 626r / min, the normal speed should be about 750r / min, so this car should also exist idle too low failure. So I think we should first idle low failure analysis. With the PGM Honda dedicated diagnostic device to read the data flow found, IAC instructions for 11%, MAP 28kPa, so the intake rate to meet the requirements. In addition, the pulse width of the fuel injection is found to be 2.62 ms, which is slightly shorter than the standard idling fuel injection pulse. At this time, the fuel is adjusted to 0.94 and the standard value is 0.90, which means that the current fuel injection pulse width Controlled by the PCM thickened, why will cause the fuel injection pulse width shorter? By the FSS (fuel system state) to close that the current fuel supply control is closed-loop control state, the possible reason is the PCM to identify the wrong conditions, that is not in accordance with idling conditions control fuel injection pulse width, but in accordance with the small load conditions control Fuel injection pulse width (because the idle conditions fuel injection pulse width is generally thickened). Through the above analysis, it can be deduced that the PCM does not recognize the idling conditions, while the supply of PCM idling signal only TP sensor, observe the TP sensor value of 26%, relative to the standard value of 10% high. TP sensor slightly adjusted, the value of the TP sensor from 26% to 11%, the idling speed increased to 750r / min, and the impact of the block damage to the solution, the test to confirm the impact of the block down also resolved. After the owner confirmed that the failure is in other repair shop after the adjustment of idle time.
    Summary: For such failures, due to the impact of the failure of the ship is relatively obvious symptoms, ignoring the other reasons, causing damage to the detours. From this case can be summed up in the confirmation of the failure to a comprehensive inspection by the engine failure caused by a lot of transmission failure, I hope you can in the future maintenance process to pay attention.