DTC P0303

2014 TOYOTA COROLLA
60,800 MILES • 4 CYL • 4WD • AUTOMATIC
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KANIVA
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In August check engine light and "trac off" lights turned on with code P0303. The car was riding rough with a lot of symptoms of a misfire. I changed the ignition coil, everything was fine. Car was driving smoothly until yesterday when same P0303 code turned on. Car was accelerating slowly and a lot of shaking movements with rough idle and acceleration. Switched out all 4 spark plugs. Drove it for a few miles fine to test out and ride was fine. However, car started again with the shaking movements and slow acceleration again and continues now. What should I do?
Oct 13, 2019 at 5:35 AM
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AL514
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Hello thanks for using 2CarPros. P0303 is a cylinder #3 misfire code. You may have a fuel injector sticking open. The reason it improved when you changed the spark plugs is because the #3 plug may have been flooded out. Replacing the plug appeared to have fix the problem because the new plug was dry, but it's probably flooded again causing the same misfire again. Pull the plugs out again and see if they're soaked in gas. Let us know what you find.
Oct 13, 2019 at 6:34 AM