Attention! 1. If the information in this section differs from that given in the underhood VECI plate, then use the data in this plate as a guide.
2. On models from 1996 and models with SFI engines, ignition timing adjustment is not provided. On models with a 4.3L V6 engine, the ignition distributor cannot be turned, but if this happens, the ignition timing will not be affected. On models with a SFI V8 engine, ignition timing adjustment is not provided; however, if the ignition distributor has been removed, it may need to be turned a little to avoid "cross-firing" in the adjacent cylinder (when the tongue of the runner is between two terminals of the ignition distributor cap, a breakdown to the adjacent terminal may occur and the engine operating order will be disrupted). A special scanner is used to adjust the distributor, therefore, the position of the distributor on these engines should be adjusted at the dealer's service center.
1. Warm up the engine. The air conditioner should be turned off.
2. Set the parking brake and block the wheels. The transmission selector should be in the Park position (on automatic transmission) or in neutral position on a manual transmission).
3. If the SERVICE ENGINE SOON indicator starts to light, then the ignition check is not allowed (see Chapter 6).
4. Before checking the ignition timing in the electronic ignition system EST, remove the relay box cover (see photo) and disconnect the brown wire with black stripes (see photo).
5. Locate the timing marks on the front of the engine (they should be visible from above after opening the hood) (see photo). There are notches or grooves on the crankshaft pulley or vibration damper. There should be a metal plate with marks and a scale attached to the timing cover. Clean the plate so that the scale is clearly visible.
6. Mark the groove on the pulley/damper with chalk or white paint.
7. Find the division on the scale of the plate that corresponds to the ignition moment specified in Technical Data, or on the underhood plate.
8. Connect the stroboscope according to the manufacturer's instructions. Almost all stroboscopes are battery powered. In addition, the stroboscope's induction sensor is placed on the high-voltage wire of the 1st cylinder.
9. Warm up the engine, switch to idle speed. Direct the stroboscope light at the scale. The mark on the crankshaft pulley should be opposite the corresponding division of the scale. If necessary, loosen the distributor mounting bolt and, slowly turning the distributor, set the ignition timing (see "Technical data"). Tighten the distributor bolt and check the ignition timing again. Access to the mounting bolt is difficult, so a special key is used to unscrew this bolt.
10. When finished, connect the wire to the relay box.