Cylinder 9 Misfire Detected

Cylinder 9 exists on engines with 10 or more cylinders, such as V10 engines found in Ford Super Duty trucks and Dodge Vipers, as well as V12 engines in luxury vehicles from BMW and Mercedes-Benz.

Yes. A flashing Check Engine Light indicates a severe misfire that can damage the catalytic converter within minutes. Pull over safely, turn off the engine, and have the vehicle towed.

Driving with an active misfire is not recommended. Unburned fuel enters the exhaust and can destroy the catalytic converter, which costs far more to replace than fixing the original misfire.

The OBD II regulation defines two separate misfire thresholds (Title 13 CCR 1968.2, section (e)(3.2)). One is misfire severe enough to damage the catalyst, evaluated in 200-revolution increments — and where the damaging rate would be under five percent, the manufacturer may simply set the limit at five percent. The other is misfire causing emissions to exceed 1.5 times the FTP standards. That is why a flashing light (catalyst-damage rate) means stop driving while a steady light for the same code does not. This is the threshold the monitor is designed around, not a description of your specific fault — the regulation says what the system must detect, not how to find it on your vehicle.