Q: Why is it still misfiring?

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Replaced the injectors, ignition module, spark plugs. Yet the car still misfires and reads code p0300 and the cel flashes when i put it in gear. Idles fine but seems to vibrate and kinda put also like to burn rich. Like strong smell of gas. Did give off codes p0137,p0138,p0400,p0440,p0441,p1138 also. I cleared them on a ocd reader. Reread codes only throwing off p0300 code now. Clueless, will drive but limited power and cel flashes.

My car has 147913 miles.
My car has an automatic transmission.

Hi there. Check the Exhaust Gas Recirculation valve on the engine. It seems to be sticking on when the engine is running at low idle and causing a misfire as the old exhaust that is burnt is reentering the engine. You may need to clean the EGR valve or replace it if the valve will not free up.

If you need further assistance with your engine having random misfires with the codes on for the EGR not working, then seek out a professional, such as one from Your Mechanic, to help you.

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