What are the reasons for the difficulty in starting a China III engine?

[VonJackson]

China III engine is difficult to start for the following reasons: Engine mechanical failure: For example, uneven cylinder pressure in each cylinder. Intake system failure: Such as air intake pipe leakage, excessive carbon deposits on the intake valve and intake pipe, excessive dirt on the throttle and the inner wall of the intake pipe, etc. Engine management system failure: For example, incorrect water temperature and intake air temperature signals, circuit failures, etc. Ignition system failure: Such as excessive carbon deposits on the spark plug or incorrect gap, leakage in the high-voltage wire and distributor cap, damaged ignition coil, etc. Fuel supply system failure: For example, the injector does not close tightly or is blocked due to excessive carbon deposits inside the nozzle.