The cup (isolator) of the ignition spark plugs must be white (light yellowish), no crack. The insulator shall be dry (i.e. without oil or gasoline) without a dense black bloom (or other colour). A light brown colour is allowed on the central electrode.
The spark plugs between the spark plugs for VAZ-2108/09/99 shall be within 1-1.1 millimetres. To check for sparks, you can buy a special probe that can be found in almost any auto shop.
