Misfire Counting Function

WARNING: This page is about a different car, the 2018 Infiniti Q60. However, it is still accessible from the selected car via links, so may be relevant.

ECM memorizes misfire counts by categorizing types of misfire as shown below.

"Cylinder-specific" combustion misfires
"Emission limit" combustion misfires
"Catalyst damage" combustion misfires

Smooth Running Signal

m/s ²	: Acceleration
t	: Time
A	: Engine running without combustion misfiring -> Acceleration values within tolerance range
B	: Engine running with combustion misfiring -> acceleration values too high
C	: Misfire counter -> starts with misfire detection

Courtesy of NISSAN NORTH AMERICA, INC.

Main factors of misfire occurrence

Ignition system
Injection system
Mechanical engine components (e.g. valve seats, valve springs, air suction)
Fuel starvation