Q: PO304

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Checked cylinder 4 for spark, no spark, Checked cylinder 3 for spark, good spark Switched cylinders 3 & 4 engine ran rough Checked spark on cylinders 3 & 4, no spark, Checked cylinder 2 for spark, good spark Switched cylinders 2 & 4 engine ran more rougher Checked for spark on cylinders 2, 3, & 4 no spark on none Seems like there is something wrong on cylinder 4, what can I do?

My car has 78000 miles.
My car has an automatic transmission.

Hello, thank you for writing in. Between the tests you have done, and the diagnostic code for a misfire on cylinder 4, you may have an issue with the ignition system. You will want to check the ignition wire, the distributor, and the spark plug for fouling. You can test the ignition wire with a spark tester. This is the safest and easier way to do so, although there are other ways. Make sure the spark plug does not have excess carbon build up or oil. These would be signs of more serious issues. While there are several other components that can cause these issues, start with these and take further diagnosis from there. For more help resolving the issue, contact our service department to schedule an appointment.

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