Possible causes

– Faulty spark plug 6
– Clogged or faulty fuel injector 6
– Faulty ignition coil 6
– Fuel injector 6 harness is open or shorted
– Fuel injector 6 circuit poor electrical connection
– Ignition coil 6 harness is open or shorted
– Ignition coil 6 circuit poor electrical connection
– Insufficient cylinder 6 compression
– Incorrect fuel pressure
– Intake air leak

Tech notes

The P0306 code means that the cylinder 6 is misfiring or is randomly misfiring. Start by checking for intake leaks an if no leaks are found the next step is to replace the spark plugs on cylinder 6. If the problem persist more tests needs to be done to diagnose problem, see “Possible Causes”

When is the code detected?

Engine Cylinder 6 is Misfiring.

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)
– Lack/loss of power
– Hard start
– Engine hesitation

P0306 Description

When a misfire occurs, engine speed will fluctuate. If the engine speed fluctuates enough to cause the Crankshaft Position (CKP) sensor signal to vary, the Engine Control Module (ECM) can determine that a misfire is occurring.

P0306 Information for specific makes

P0306 BMW
P0306 DODGE
P0306 CHRYSLER
P0306 JEEP
P0306 HONDA
P0306 ACURA
P0306 HYUNDAI
P0306 INFINITI
P0306 NISSAN
P0306 ISUZU
P0306 KIA
P0306 SCION
P0306 TOYOTA
P0306 LEXUS
P0306 MAZDA
P0306 MITSUBISHI
P0306 SUBARU
P0306 VOLKSWAGEN
P0306 AUDI
P0306 GMC
P0306 PONTIAC
P0306 CHEVROLET
P0306 FORD
P0306 CADILLAC
P0306 BUICK
P0306 SATURN
P0306 MERCURY
P0306 VOLVO
P0306 HUMMER
P0306 JAGUAR