The intent of the specification is to present a functional set of requirements which define the user and hardware interfaces
while providing sufficient capability to meet the misfire patterns for compliance demonstration and engineering
development. The misfire generator behaves as a spark-defeat device which induces misfires by inhibiting normal ignition
coil discharge. It does so by monitoring the vehicle’s ignition timing signals and suspends ignition coil saturation for
selected cylinder firing events. The misfire generator will thereby induce engine misfire in spark ignited gasoline internal
combustion engines; including rotary engines.
This requirement assumes that the user has a fundamental understanding of misfire diagnostics as well as ignition
controls. This requirement is not intended to be an introductory misfire guideline or interpretation of regulatory
Rationale: This SAE Recommended Practice provides performance requirements and guidelines for misfire generators for spark
ignition misfire generators. It is applicable for common types of ignition based misfire generators.
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