Q: Car jerks forward slightly everytime I hit 19 mph

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Keep getting cylinder misfires and codes for cat convertor so I replaced all the coils spark plugs and cat during that time my car started to jerk everytime I hit around 19 mph after acceleration from a stop and then once it started smoking (white)from the tailpipe and jerking really bad took to the dealer they said misfire in cylinder 3 cleaned the wetness on the spArk plug moved the coils around ,have not seen the smoke since . Car still jerks everytI me at 19 mph and car smell raw fuel occasionally unless i press the gas alittle harder i dont get the jerk at 19mph.Took it back they said threw a code for o2 sensor behind left cat , replaced it but still having same issue. My car has 169000 miles. My car has an automatic transmission.

My car has 169000 miles.
My car has an automatic transmission.

Hello, and thank you for writing in. The misfire needs to be the focus of our attention. If you had moisture on the spark plugs and white smoke, then there is some kind of coolant leak. This fouling on the spark plugs may be related to the leak, and although you do not see the smoke, the plugs may still be wet. Check this first. Simply moving the spark plug wires around would not have solved a coolant leak. Moisture in the exhaust would also cause the catalytic converter and the oxygen sensors to show they are not working correctly, as they are used to processing water vapor, but not coolant. Have you checked the level of your coolant? Then you can turn your attention to the ignition system, and the fuel delivery system. For more help resolving the issue, contact our service department.

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