P0310: Cylinder 10 Misfire Detected

What does P0310 mean?

The engine module detects misfire from crankshaft speed: a cylinder that does not fire gives no acceleration impulse. At a catalyst-damaging rate (CARB: at least 5 % per 200 revolutions) the warning light flashes; at an emissions-relevant rate (at least 1 % per 1,000 revolutions – GM about 2–5 %, Ford 0.9–1.5 %) it comes on after two trips. Ford and GM may shut off a misfiring cylinder's injector to protect the catalyst. P0310 means more than 90 % of the detected misfires fall on cylinder 10. Usual causes are the ignition coil or spark plug of that cylinder, its injector, or low compression; a quick test is to swap coil or plug with a neighbouring cylinder and see whether the misfire moves. Cylinder 10 exists on ten-cylinder engines such as Ford's 6.8 litre V10; there an under-torqued crankshaft pulley bolt and engine software caused false misfire codes on all cylinders.

The code tells you which monitor failed, not which part is broken. Test before replacing parts.

Symptoms

• Check engine light on, flashing at a catalyst-damaging rate
• Rough idle, jerking, vibration
• Loss of power, hesitation
• Smell of unburnt fuel, higher consumption

Common causes

• High Ignition coil of cylinder 10 faulty (coil, connector, ground)
• High Spark plug of cylinder 10 worn, sooted, cracked or wrongly gapped
• Medium Injector of cylinder 10 clogged or leaking, or its control
• Low Low compression on cylinder 10 (valve, rings, head gasket) or local false air
• Low Water or oil in the plug well

Likelihood is a general estimate across vehicles; your make and model may differ.