4. Difficult cold start Common trouble location: 1. Fuel with water; 2. Fuel pump; 3. Coolant temperature sensor; 4. Fuel injector; 5. Ignition coil; 6. Throttle body and idle speed by-pass air way; 7. Mechanical part of the engine. Diagnosis Flow Table 1-70 91 S/N Operation Test Results Actions 1 Connect the fuel pressure gauge (the connection point is the front end of the intake pipe of the fuel distribution pipe assembly), and start the engine. Check if the fuel pressure of the engine under full working condition is about 380kPa. Yes Next step No Check and repair fuel supply system 2 Draw out the wire of one of the cylinders, and connect with the spark plug.
Keep the electrode of the spark plug about 5mm from the engine body. Start the engine, and and check if the blue white high voltage fire is produced. Yes Next step No Check and repair ignition system 3 Disconnect the coolant temperature sensor, and start the engine. Is it OK? Connect a 2500Ω resistance in series at the connection point of the coolant temperature sensor to replace the sensor, and start the engine. Is it OK? Yes Replace sensor No Next step 4 Gently step on the accelerator. Does it can be started easily? Yes Wash throttle and idle speed air way No Next step 5 Remove the fuel injector.
Check the fuel injector for leakage or blockage with a special fuel injector cleaner & analyzer. Yes Remove the trouble No Next step 6 Check the fuel for normal operation. Yes Replace fuel No Next step 7 Check the pressure of each cylinder of the engine. Check if the pressure is enough. Yes Remove the mechanical troubles for the engine No Next step 8 Connect the electronic injection system adapter. Turn on the ignition switch. Check the power supply of the pin 12#, 13#, 44#, 45#, 63#. Check the grounding of the pin 3#, 51#, 53#, 61#, 80#. Are they OK? Yes Diagnosis help No Check and repair relevant line