1. Severe carbon deposition on the throttle valve: carbon deposition on the throttle valve will affect the perception of the throttle and air intake volume, resulting in delayed or even incorrect computer transmission signals, which will cause the vehicle to fail to start
 2. Dirty fuel injection nozzle: it is easy to stick some gum on the fuel injection nozzle, which will block the normal fuel injection volume, resulting in poor gasoline atomization, which will delay the ignition and make it difficult to start the car
 3. Spark plug carbon deposition: if there is more carbon deposition on the spark plug or there is air leakage at the joint between the metal and the porcelain body, it will cause poor ignition
 4. Dirty battery: Dirty battery terminals may also cause poor conductivity, which may affect ignition. Of course, insufficient battery power may also cause delay in ignition startup.