Note. The procedure described below is only for checking the basic settings made at the factory. The possibility of adjustments is not provided, therefore, the only purpose of this test is to assess the correct functioning of the onboard processor. If during the diagnosis of the ignition system (see Section Check of functioning of system of ignition) 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 driven 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, look for the VECI label under the hood and carefully read the instructions for setting the ignition timing. Of particular importance is the correct setting of the idle speed, since the engine speed is directly related to the ignition timing. Prepare all the necessary tools.
- 1 - Vacuum plugs - All detachable vacuum hoses must be plugged immediately. For this purpose, plugs of various sizes and configurations are produced
- 2 - Stroboscope with inductive connection - Provides a pulse of a bright, highly directed beam, synchronized with the moments of sparking on the electrodes of the spark plug of the first cylinder. Connect to the BB 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 clamping bolt is limited and its release using a conventional wrench becomes extremely difficult
4. With the ignition off, connect the stroboscope according to the manufacturers instructions. The stroboscope is usually powered by an on-board battery. The receiving inductive lamp sensor is installed on the BB wire of the spark plug of the first cylinder (see Specifications to Chapter Engine).
5. Use a jumper wire to short-circuit terminals 8 and 13 of the diagnostic connector (DLC), - this will put the PCM in basic ignition timing mode.
6. Find the timing marks on the crankshaft pulley.
7. Start the engine warmed up to normal working temperature and direct a stroboscope beam to the adjusting pointer.
8. The red mark illuminated by the strobe beam on the crankshaft pulley, while remaining motionless, should be aligned with the pointer.
9. If there are violations in the settings, drive the car to a service station to perform PCM diagnostics.
10. Stop the engine and remove the stroboscope.
11. Remove the jumper wire from the terminals of the diagnostic connector.