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Q: My automatic 2009 Jeep Wrangler shows 4 codes: P0562, P0306, C00377 & B2100.

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Should I change the ignition coil or just the plug wires and spark plugs? I am using synthetic oil. Regarding the low voltage, my battery shows 10V so I believe i need a new battery as well, What are your thoughts?

My car has 134300 miles.
My car has an automatic transmission.

A: Hi there, thanks for writing in. I would su...

Hi there, thanks for writing in. I would suggest replacing the battery first. A battery at 10V usually means one of the cells has failed. The P0306 code points out a misfire on cylinder 6. Since it is only one cylinder, have your spark plugs checked for signs of wear. Replace the spark plugs and spark plug wires at the same time. The technician can try taking the #6 wire from the coil while the engine is running to check for spark from the coil. If there is no spark, have the technician replace the coil. If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this issue for you, and make or suggest any repairs as needed.

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