1. In the event of a malfunction of the injection system, first of all, check the condition and reliability of fastening of the contact connections of the corresponding electrical circuits. Then check the condition of the air cleaner element, spark plugs (do not forget to check the setting of the interelectrode gaps), hoses of the crankcase ventilation system, compression pressure in the cylinders and the setting of the ignition timing.
2. If during the listed general checks it is not possible to identify a malfunction, the car should be driven to a service station for deeper diagnostics using special equipment. This test reads the memory data of the ECU self-diagnosis module. Trying to check the status of each of the components of the system one by one on your own is extremely inefficient and can only be a waste of time and effort, especially if the malfunction is dynamic in nature. In addition, the risk of accidental irreversible damage to the ECU is too great.
3. Sufficiently experienced amateur mechanic with all the necessary equipment (accurate tachometer and gas analyzer) can independently check the level of CO in the exhaust gases and the engine speed at idle. If the parameters taken are outside the permissible ranges, the car should be driven to a service station for further diagnostics. Manual adjustment of the quality of the mixture and the number of idling revolutions are not provided. Negative results of check testify to internal infringements of system of injection of fuel.