P0301 on a Honda: 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 Honda

On a Honda, P0301 means the engine computer has detected that cylinder 1 is not firing properly and is failing to contribute its share of power. Because it is a single-cylinder code, the problem is almost always something specific to cylinder 1, like its spark plug, ignition coil, or fuel injector.

Is P0301 common on Hondas?

P0301 is common on higher-mileage Hondas, especially the Civic, Accord, and CR-V with 1.5L turbo and 2.0L or 2.4L engines. Honda's iridium spark plugs last a long time but eventually wear out, and coil-on-plug ignition coils can fail with age. When only one cylinder misfires, swapping parts between cylinders is a quick way to confirm the culprit.

Commonly reported on: Civic, Accord, CR-V, Pilot.

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 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 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

Frequently asked questions

Is it safe to drive my Honda with a P0301 code?

Only if the light is steady and the car runs fine. A flashing light means a severe misfire, so stop driving and get it towed.

Why does my Honda misfire on cylinder 1?

The spark plug, ignition coil, or fuel injector for that cylinder is usually at fault. These parts wear out over time, especially on high-mileage Civics, Accords, and CR-Vs.

How much does it cost to fix P0301 on a Honda?

A spark plug is usually under $150. A coil runs a bit more, and a fuel injector is the most expensive of the three.