P0310: Cylinder 10 misfire evidence depends on the evaluation window

P0310 identifies cylinder 10 within Ford's documented general and cylinder-specific misfire code range. The monitor evaluates misfire rates over repeated engine revolutions; it does not name the ignition, fuel or mechanical component responsible for the irregular combustion.

Two rate windows answer different questions

Ford calculates catalyst-damage-related rates over 200 revolutions and emissions-related rates over 1,000 revolutions. The source's Mode $06 table also distinguishes current-cycle counts, a weighted history and rates captured when a code changes state. Those values describe different time windows and should not be compared as though they were one simultaneous measurement.

A useful record includes the cylinder-specific count, total misfire rate, load and engine speed. The catalyst-damage limit varies with operating conditions, so one published percentage is not a universal severity threshold.

Check whether the monitor was eligible

The strategy relies on crank and cam signals and learned profile corrections. Rough-road detection, fuel cutoff and rapid torque changes can temporarily disable evaluation. A lack of new counts during an excluded interval is not evidence that combustion is healthy.

Confirm that the actual engine has the relevant cylinder numbering before locating a component. The OBD summary does not provide a cylinder-location diagram or establish a failed coil, injector or spark plug. Verification should show acceptable cylinder-specific behavior after the monitor resumes under valid conditions, rather than relying only on a cleared warning or a brief smooth idle.

Source and applicability

This explanation covers the cited Ford monitor variants, not every vehicle displaying this code. Match the engine, sensor architecture and calibration before applying numerical limits.

Ford OBD summary, PDF page 10, Ford OBD summary, PDF page 11.