Q: Misfire P0304 and shaking

asked by on October 28, 2016

Cold engine everything OK. Warm start shaking on idle. Shaking is increasing and becoming ok. injector been cleaned ultrasoud . Changed plugs, vt leads, coil. Can't see so far drop of power

My car has 70000 miles.
My car has a manual transmission.

Hi there. From the description you have provided, your vehicle’s P0304 misfire needs to be properly diagnosed since replacing components is not working. It could be low compression in that cylinder. This could account for not feeling the miss cold.

Increased RPM can overcome slightly low compression. A compression test should be performed, to rule out a mechanical failure. It could also be a faulty fuel injector electrically failing with increased temperature.

Resistance increases with an increase in temperature. It could be a poor electrical connection again, showing up with increased temperature. Circuit tests should be performed. I recommend having you vehicle’s Check Engine Light diagnosed and repaired by a certified technician, such as one from YourMechanic.

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