Misfire CEL DTC P0300, P0301, P0302

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Misfire CEL DTC P0300, P0301, P0302

Post by warpc0il » Fri Oct 04, 2019 2:21 pm

All these code indicate a misfire, either general (P0300) or specific to the front (P0301) or rear (P0302) rotors.

"Misfire" just means that the power pulse detected by the Eccentric Shaft Sensor are uneven, as measured by the PCM.

These can be caused by bad ignition components, they can also be due to fuel injectors or low fuel pressure, which in turn can be down to a failing pump, loose connection, blocked filter or damaged low-speed resistor.

The other common cause of misfire codes is a bad signal from the ESS.
This can be a loose/corroded connection on the ESS, something magnetic stuck to the outside of the ESS or an internal ESS failure, any of which can not only trigger the code but create the symptoms of a misfire.
Dave
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