Symptom: engine starting bad, from the car when breathing.
    Troubleshooting: a preliminary investigation, the front bumper loaded with a tow hook, the car itself, the battery completely discharged, assistant seats also stood a group of fully discharged battery. First replace the battery, change the battery to start the engine, starting the motor dragging the handle dry, the engine did not even the initial explosion, completely start not up. From the crank when the engine sound to judge, there is compression pressure, timing belt is not broken. Investigate the ignition system, the normal light flashes. Remove the spark plug test, ignition spark normal.
    Then investigate the fuel system, a look at the fuel pulsation damper, the dampers of the screw head did not drum out, high-pressure tubing and no tension, as if there is no fuel pressure.
    The engine is a 4A-GEU engine, the fuel injection system known as the EFI-D (D-type electronic control fuel injection system), the use of vacuum sensor air flow meter. As the crank handle, the distributor to the ECU output engine rotation signal (Ne signal), ECU received the signal, turn on the line, the line relay relay action, driving fuel pump running pump oil. However, even if the use of centralized one-piece short connector directly to the fuel pump power, fuel pump does not move. Since the fuel pump does add the normal voltage, the fuel pump does not move, then the problem must be on the fuel pump itself. With a screwdriver from the fuel pressure gauge interface into the gently tapping, fuel pump rotation, so you can conclude that the internal actuator lock.
    After the fuel pump is replaced, the engine will start smoothly. In the operation test confirmed that the engine no load acceleration is no problem, but in the engine when the engine respite, and the engine idling speed is not uniform, that is idle instability. Check the fuel pressure, idle at 250kPa, fuel pressure through the regulation of the fuel pressure after the 200kPa, no load acceleration does not decline, the fuel system is normal.
    Survey ignition advance angle, BTDC (top dead center) is 30 °. Advance angle so much, there may be a timing belt difference a tooth. Open the timing belt cover, a look at the mark was very accurate, into the exhaust valve timing is also normal. Shorted from the diagnostic connector T terminal, ignition advance angle with a little change are not. Check the self-diagnosis system, the results of self-diagnosis system output fault code is 11, said switch signal system anomalies. The investigation of each switch, the result is the throttle sensor idle contact contact is not on.
    This kind of car breathing and idle bad can be explained. Adjust the idle contact found that, in any case, the contact is not on the idle contact. Removed to check, the sliding part does not work, become completely unable to reset the state. The throttle sensor decomposition of the sweep, to the sliding parts with lubricating oil to make a good reset. Again to adjust the idle contact, to restore the normal state, maintenance work is over.
    Fault analysis: throttle sensor is a linear type of component, with the throttle opening change the output signal voltage linear changes. If the output signal voltage is constant at 5V or 0V, it means a wire break or a short circuit, and the self-diagnosis system can diagnose and output the corresponding code. But the problem of idle contact, self-diagnosis it was placed under the switch signal system. The fault, the sensor output signal voltage is changed, only the idle contact can not be connected. The electronic fuel injection system does not perform idle compensation and can not control the ignition advance angle at idle speed. Since there is no idle contact ON → OFF signal, it is impossible to perform fuel injection compensation when starting from the vehicle.