P0301 on a Ford: Causes, Fixes & Repair Cost

🟠 Moderate severity · drivable

If the check engine light is flashing, stop driving — a severe misfire can damage the catalytic converter. A steady light is usually safe for a short drive to a shop.

What P0301 means on a Ford

On a Ford, P0301 means the engine computer has detected that cylinder 1 is not firing properly and is failing to contribute its share of power. Because the code names one cylinder, the fault is usually specific to cylinder 1, such as its spark plug, ignition coil, or fuel injector.

Is P0301 common on Fords?

P0301 is common on Ford EcoBoost engines and V8s, including the 3.5L in the F-150 and Explorer and the 4.6L and 5.4L V8s in the Mustang and older F-150s. Ignition coils and spark plugs wear with mileage and are the usual suspects. A bad coil boot on a coil-on-plug setup can also cause a single-cylinder misfire.

Commonly reported on: F-150, Explorer, Mustang, Escape.

Symptoms

Check engine light on (flashing if severe)
Rough idle or shaking at a stop
Loss of power or hesitation under acceleration
Poor fuel economy

Common causes

most common: Worn or fouled spark plug in cylinder 1
common: Failing ignition coil or coil boot for cylinder 1
common: Clogged or leaking fuel injector in cylinder 1
less common: Vacuum leak near the intake
less common: Low compression in cylinder 1 from engine wear

How to fix it

Fix	DIY?	Typical cost
Replace the spark plug in cylinder 1	Yes	$30–120
Replace the ignition coil or coil boot for cylinder 1	Yes	$80–300
Clean or replace the fuel injector in cylinder 1	Mechanic	$150–600
Run a compression test to rule out internal engine wear	Mechanic	$100–200