Checking and adjusting the fuel injection system «MONO-JETRONIC» (VW Passat B4)

To check and adjust the injection system "Mono-Jetronic" to avoid injury and damage to system components, you must follow these rules.

Do not operate the engine if the wire clamps are not securely fastened to the battery terminals.

Do not disconnect the wires from the battery terminals while the engine is running.

It is necessary to disconnect the battery from the vehicle's electrical system when charging it in a vehicle from an external power source.

Do not start the engine using an external power source with a voltage greater than 12 V.

Do not disconnect the electrical connector of the electronic control unit when the ignition is on. Before connecting the plug connectors, make sure that there is no damage or oxidation on the contacts of the plug and socket parts, and that the connectors are securely connected. Make sure that the rubber pad seal and the retaining spring are present. Replace the damaged spring.

Before carrying out work on the vehicle using electric welding, including spot welding, disconnect the connector of the electronic control unit.

Remove the electronic control unit if the vehicle will be exposed to temperatures above 80°C (for example, before placing a freshly painted car in a drying chamber). Before checking the compression in the engine cylinders, disconnect the wire connectors from the injectors to prevent fuel from being supplied to them.

Do not check the wires and their connections with a test lamp.

Do not check for voltage in the circuit "for spark".

Before checking the voltage, make sure the battery is fully charged. Before checking the resistance, make sure the ignition is off.



In addition, on vehicles with an exhaust gas neutralizer, the following rules must be observed:

• use only unleaded petrol;
• do not allow the fuel to run out completely;
• if the engine starts to malfunction, it is recommended that you do not use the vehicle and fix the problem as soon as possible;do not disconnect the spark plug wires while the engine is running:
• when testing a car on a stand with running drums, ensure good airflow to the neutralizer;
• when carrying out checks with the ignition system disconnected or faulty, disconnect the wire connectors from the injectors.

(View the original article on the resource: www.vwmanual.ru)