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Q: Rough idle, smoking,CEL on

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My 2000 celica is smoking, getting misfire codes and idling so low that it dies. Pulled codes (p0300,301,303,304) replaced all plugs and checked coil packs(good). There is lots of smoke and the smell of gas is terrible. I looked around for possible exhaust and air leaks but found none. Please help

My car has 150654 miles.
My car has an automatic transmission.

Hi there. The P0300 OBD-II trouble code typically indicates that there is a misfire in random or multiple cylinders. The other codes indicate that the misfire is being registered in the first, third and fourth cylinder. This is most likely why you’re engine is running rough. The best thing to do is have a professional mechanic complete a car is running rough inspection, so they can determine why the cylinders are misfiring and causing the symptoms you’ve described above.

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