Spark plug

With some experience in the appearance of the spark plug, conclusions can be drawn about the operational condition and the need for engine adjustments. Moreover, if the electrodes and the body of the insulator:

• gray, this indicates the normal operation of the candles and the normal composition of the mixture;
• black, then this indicates an enriched mixture;
• light gray, then this indicates a lean mixture;
• oily, this indicates the failure of the candle or poor sealing of the piston rings (check compression).

Spark plugs can be cleaned with a brass brush or sandblaster.

The interelectrode distance of the spark plug depends on the type of engine.

A sign that the wear limit of platinum spark plugs has been reached is when the center electrode is no longer visible in the insulating base. In this case, the spark plugs must be replaced.

General information about the candles used is given in Table. 8.

Note: New extended life spark plugs can only be installed on vehicles with a TSZ-H ignition system with an upgraded ignition coil. The design of the ignition coil is marked with a certain color of the sticker, see table. In case of doubt, consult a service station.

Table 8. Spark Plugs

1 with a green sticker on the ignition coil.
2 with a gray sticker on the ignition coil.
3 ignition coil without sticker.
4 replacement interval 15,000 km.