Cylinder 12 Misfire Detected

You can drive short distances with a steady Check Engine Light. If flashing, pull over immediately to prevent catalytic converter damage.

Yes. On V12 engines, cylinder 12 is the last cylinder, typically located at the rear of one bank. It is often the hardest to access due to its proximity to the firewall.

If you can access the cylinder, replacing a spark plug or ignition coil is a straightforward DIY task. However, V12 engine bays are very tight, and some cylinders may require significant disassembly to reach.

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.