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Q: Bad gas

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Went to put some gas in my car,before that car running fine,about 15 min,after that,car started hesitating,jurking,rough idling,had the car put on the machine,code po305 was told that ignition coil and spark plug need to be addressed,will bad gas cause that problem.

My car has 120000 miles.
My car has an automatic transmission.

A: You may have got some gas that has some wat...

You may have got some gas that has some water in it since problem started real soon after refueling. The issue would be is would bad fuel cause only one cylinder to misfire? It is not likely that it would. You would get random misfires from random cylinders and other codes like P0300 for random engine misfires. I would recommend having a mechanic like one from YourMechanic come to you and check the coil and plug for cylinder number 5 to see why only that cylinder is misfiring. You may find the engine needs a spark plug and coil replacement to fix the issue but will need to narrow down the diagnosis first.

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