The difficulty of engine starter me

The difficulty of engine starter means that the starter can drive the engine to run normally, but the engine cannot be started or needs to be started repeatedly or rotated for a long time to start. To enable the engine to start normally, it must have three conditions: sufficient ignition energy, correct ignition timing, proper concentration of mixture, and normal cylinder compression pressure. If one of these conditions cannot be met, it will cause the engine to fail to start or difficult to start. In general, when repairing such faults, the following items need to be checked: perform self-diagnosis of the fault and check for the fault code. Check whether the starter can turn when starting. If it is checked that the starter is not running, first check the battery power and starting circuit. If the starter can turn but the engine cannot run, check the meshing part of the starter with the engine and the mechanical parts of the engine. If the accelerator pedal is pressed to the middle opening position and restarted, the engine can start, indicating that the fault should be a problem with the idling control system or a leak or clogging of the intake pipe or a problem with the fuel supply system (such as excessive gas mixture). Check whether the spark plug is sparking when starting. If there is no spark or the spark is weak, check the ignition system. Check whether the fuel supply to the fuel system is normal. Check whether the sealing, connection and operation of the EGR system are normal. During engine starting and idling, the exhaust gas recirculation system should be completely closed. If the EGR valve is opened by mistake during engine starting or idling for some reason, it will cause fresh air that actually participates in combustion The amount is reduced and the air-fuel mixture is too lean, which may cause difficulty or failure to start the engine. Check that the engine coolant temperature sensor circuit and resistance value meet specifications. Check the intake manifold absolute pressure (or mass air flow sensor) for problems. Check the clearance and resistance of the crankshaft position sensor. Check basic engine mechanical problems