P0306

Cylinder 6 Misfire Detected

Ignition / misfire Generic OBD-II High

What it means

P0306 means the engine control module detected a misfire specifically in cylinder 6 — fuel isn't burning properly there, so the engine runs rough and loses power. The most common causes are a worn spark plug or a failing ignition coil on that cylinder. A sustained misfire can overheat and damage the catalytic converter, so fix it promptly.

High

Can I keep driving? Not for long — a flashing check-engine light means cylinder 6 is actively misfiring; drive as little as possible to avoid catalytic converter damage.

Real-world scan data

Seen in

548

scans in the past year

Found in

0.1%

of scans

0.1%

of scans that found faults

Appears alongside · share of P0306 scans

P0300in 66.4% of scans

P0305in 34.5% of scans

P0304in 32.9% of scans

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Check-engine light on (often flashing during an active misfire)
Rough idle, shaking, or vibration
Reduced power and hesitation on acceleration
Increased fuel consumption

Common causes

Most likely first

Worn spark plug in cylinder 6Likely
Failing ignition coil on cylinder 6Common
Clogged or leaking fuel injector on cylinder 6Common
Vacuum leak or low fuel pressure affecting that cylinderLess often
Low compression in cylinder 6 (valve or ring wear)Less often
Faulty ECM (rare)Less often

How to diagnose & fix

Work through it in order

Read freeze-frame data to confirm the miss is on cylinder 6.
Swap the coil and plug with an adjacent cylinder — if the misfire follows, you've found it.
Replace the worn spark plug and/or ignition coil for that cylinder.
Test the injector for that cylinder and check fuel pressure.
If it persists, run a compression test for mechanical causes. Clear and re-test.

FAQ

Quick answers

Is it safe to drive with P0306?+

No — especially with a flashing light. An active misfire can quickly overheat and destroy the catalytic converter.

Can I just clear P0306?+

It returns within a few drive cycles until the plug, coil, injector, or compression issue on cylinder 6 is repaired.

Read & clear P0306 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX