Saab Direct Ignition

Saab Direct Ignition is a Capacitor discharge ignition system developed by Saab Automobile, then known as Saab-Scania, and Mecel AB during the nineteen eighties. It was first shown in 1985 and put into series production in the Saab 9000 in 1988. The system have been revised several times during the years and is still in production today. The ignition system together with the ignition coils form a single cassette (or two cassettes in the case of a V6 engine) which is placed directly on the spark plugs. The system put a low voltage over the spark plugs when they aren't fired to measure ionization in the cylinders. The ionic current measurement is used to replace the ordinary cam phase sensor, knock sensor and misfire measurement function.