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Q: Car running on seven cylinders

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My car seems to be running on only seven cylinders. I replaced all of the spark plugs and wires. The local shop says I need a new PCM, but I am not sure.

It is possible that the PCM may be at fault. However, I would be more suspect of the ignition coil for the cylinder that is not firing. I would ask for help from one of the mechanics at YourMechanic to come to you, check the ignition system, and see if the coil needs to be replaced.

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