Another important bit of 1987-1989 electronic engine management data is constantly transmitted from your L98 Knock Sensor. This microphone constantly "listens" for engine knock under load and occasionally caused by poor quality fuel. When it detects a "spark knock", it signals the ECM for an ignition timing correction. The knock is eliminated and the fuel is consumed more efficiently.
With the aid of the Corvette Knock Sensor Tool (601-084) and a Digital Engine Analyzer (106-305) you can easily test the knock sensor for peak performance.
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