Note: The procedure described below is intended only to check the basic settings made at the factory. No adjustments are possible, therefore, the only purpose of this test is to assess the correct operation of the on-board processor. If during the diagnostics of the ignition system (see Section Checking the functioning of the ignition system) it is not possible to identify the reasons for the violation of the ignition timing settings, the PCM should be replaced, for which the car must be taken to a service station.
1. Start the engine and warm it up to normal operating temperature.
2. Check and, if necessary, adjust the idle speed (see Chapter Settings and ongoing maintenance).
3. With the ignition off, locate the VECI label under the hood and carefully read the instructions on setting the ignition timing. It is especially important to set the idle speed correctly, as the engine speed is directly related to the ignition timing. Prepare all the necessary tools.
- 1 - Vacuum Plugs - All disconnected vacuum hoses must be plugged immediately. Plugs of various sizes and configurations are available for this purpose
- 2 - Stroboscope with inductive connection - Provides pulsation of a bright, highly focused beam, synchronized with the moments of spark formation on the electrodes of the spark plug of the first cylinder. Connects to the high-voltage wire of the spark plug of the first cylinder in accordance with the manufacturers' instructions
- 3 - Special wrench - On some models, access to the distributor clamp bolt is limited and it becomes extremely difficult to loosen it using a regular wrench
4. With the ignition off, connect the stroboscope in accordance with the manufacturers instructions. The stroboscope is usually powered by the on-board battery. The inductive receiving sensor of the lamp is installed on the high-voltage wire of the spark plug of the first cylinder (see Specifications in Chapter Engine).
5. Using a jumper wire, short-circuit terminals 8 and 13 of the diagnostic connector (DLC) together - this will put the PCM into the basic ignition timing setting mode.
6. Locate the timing marks on the crankshaft pulley.
7. Start the engine at normal operating temperature and point the strobe light at the timing indicator.
8. The red mark on the crankshaft pulley illuminated by the stroboscope beam, while remaining stationary, should be aligned with the pointer.
9. If any faults are found in the settings, take the vehicle to a service station to have the PCM diagnosed.
10. Turn off the engine and remove the stroboscope.
11. Remove the jumper wire from the diagnostic connector terminals.