1.6.1.2 Similar Conditions Function

When the engine management system identifies a failure in the misfire system or in the fuel system, the engine management system is required to record the conditions present when the fault occurred. These conditions recorded include engine speed, engine load (MAF), and the warm up status of the first event that resulted the fault code storage. These stored conditions are referred to as similar conditions  .

When the similar conditions are met without a failure in either the misfire or the fuel system, the flag is set to 1. When this flag is set, the driving cycle counter for that failure can be decremented.

The code and stored freeze frame conditions may be erased when similar conditions are not encountered during the subsequent 80 driving cycles immediately following the initial malfunction detection.

The MIL can be extinguished after three sequential driving cycles in which similar conditions have been encountered without exceeding of the fuel system diagnostic thresholds.