P0339 — Crankshaft Position Sensor A Circuit Intermittent

What Does P0339 Mean?

P0339 is a diagnostic trouble code indicating: Crankshaft Position Sensor A Circuit Intermittent. This code relates to the ignition system system. It has been reported in NHTSA complaints across 4 different vehicle models.

Engine misfires are detected by monitoring crankshaft rotational speed variations. Each cylinder's power stroke produces a characteristic acceleration pattern. When a cylinder fails to fire, the crankshaft decelerates during that cylinder's stroke. The ECM identifies which cylinder misfired and how often. P0313-P0399 codes cover extended misfire monitoring including lean misfire detection, knock-related ignition faults, and secondary ignition monitoring. A flashing check engine light during active misfires is an emergency — raw unburned fuel enters the catalytic converter, potentially destroying it.

Symptoms of P0339

⚠️ Check engine light on (may flash during active misfire)
⚠️ Engine misfiring — rough idle, stumbling, shaking
⚠️ Loss of power during acceleration
⚠️ Increased emissions and fuel consumption
⚠️ Catalytic converter damage if ignored
⚠️ Possible engine vibration at idle

Common Causes

🔍 Worn or fouled spark plugs
🔍 Faulty ignition coil
🔍 Vacuum leak causing lean misfire
🔍 Fuel injector issue (clogged, leaking, or electrical)
🔍 Low compression (worn rings, burned valve, head gasket)
🔍 Incorrect ignition timing

P0339 Reports by Year

2023

3

2018

2

2020

2

2019

2

Real Owner Reports

From NHTSA complaint database — actual owner descriptions.

"THE CAR HAS STALLED THREE TIMES, TWICE ON THE HIGHWAY, ONCE LOSING POWER STEERING. TWICE ACCELERATING AT 5 AND 50 MPH AND ONCE IDLING AT 30 MPH. BATTERY AND CHARGING SYSTEM ERRORS ON DASH. EACH TIME, PULLING OVER, GOING TO PARK, AND RESTARTING WORKS. CRANK POSITION SENSOR WAS REPLACED AFTER SECOND S"
— Toyota Camry owner, 05/15/2018

"I OWN A 2015 DODGE JOURNEY 63000 MILES. WHEN THE VEHICLE WAS IN MOTION ON A MAJOR STREET TRAVELING 49MPH THE CAR JERKED, DEACCELERATED ABRUPTLY AND THE STEERING WHEEL BECAME TIGHT. IT DID NOT SLOW DOWN IT DEACCELERATED. THERE WAS NO WARNING OR CODE ON PRIOR TO THIS HAPPENING. I WAS LUCKY THERE WAS "
— Dodge Journey owner, 08/30/2020

"WHILE DRIVING, CARS ENGINE SHUT OFF. I WOULD TRY TO START IT, SOMETIMES IT WOULD START BACK UP AGAIN I WOULD DRIVE IT AND THEN THE ENGINE WOULD SHUT OFF AND SLOWLY STOP MOVING. CAR WAS DIAGNOSED WITH THE ENGINE CODE P0335 AND P0339 CRANKSHAFT POSITION SENSOR MALFUNCTION/INTERMITTENT. WITHIN THE SAME"
— Jeep Compass owner, 04/05/2019

Source: NHTSA Complaints Database

Most Reported Vehicles for P0339

Based on NHTSA owner complaint data.

#	Vehicle	Reports
1	JEEP COMPASS
2	JEEP PATRIOT
3	DODGE JOURNEY
4	TOYOTA CAMRY

P0339 Reports by Vehicle

Detailed NHTSA complaint analysis for each vehicle model.

DODGE JOURNEY

2 NHTSA reports · Peak: 2015

JEEP COMPASS

3 NHTSA reports · Peak: 2012, 2016, 2018

JEEP PATRIOT

3 NHTSA reports · Peak: 2012, 2015, 2016

Diagnostic Tips

Check misfire counters in Mode 6 data — identifies which cylinder(s) are misfiring most
Swap ignition coil to another cylinder — if misfire follows, coil is bad
Check spark plugs — worn electrode, fouled with oil or carbon, cracked insulator all cause misfires
Perform compression test on affected cylinder(s) — low compression means mechanical issue

Common Mistakes to Avoid

❌ Replacing coils without checking spark plugs — a worn plug will kill a new coil
❌ Ignoring a flashing check engine light — this means severe misfire that's damaging the catalytic converter NOW
❌ Replacing ignition parts when the misfire is caused by a vacuum leak or low compression

Frequently Asked Questions

What does a flashing check engine light mean?

A flashing CEL means severe, active misfire that risks catalytic converter damage. Pull over safely and reduce engine load. Do not rev the engine. Drive gently to a repair facility or have it towed. This is the only CEL condition that warrants immediate action.

Can misfires damage my engine?

Misfires themselves don't usually damage the engine, but they can destroy the catalytic converter ($1000-$3000). Severe misfires also dilute engine oil with raw fuel, reducing lubrication. Extended misfires should always be repaired promptly.

Why does my car misfire only when cold?

Cold misfires are often caused by slightly worn spark plugs (gap too wide for cold, dense air-fuel mixture), marginal ignition coils that work fine once warm, or small vacuum leaks that are more noticeable at cold idle RPM.

What To Do Next

Possible Fixes

🔧 Replace spark plugs
🔧 Replace ignition coil(s)
🔧 Repair vacuum leak
🔧 Clean or replace fuel injector
🔧 Engine mechanical repair (valves, rings, gasket)

1
Find your vehicle above
Click your make and model for real owner reports and common causes specific to your vehicle.
2
Check for recalls
Go to nhtsa.gov/recalls and enter your VIN. Free repairs if covered.
3
Get a professional diagnosis
A code alone doesn't identify the exact failed part. A diagnostic ($50–$150) pinpoints the root cause.

P0339: Crankshaft Position Sensor A Circuit Intermittent