Q: Engine coil was changed light is back on

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a engine coil #3 was changed 2 months ago, same code came back

My car has 79000 miles.

This may be a result of another ignition coil failing. Ignition coils are coated with a varnish-like insulation that becomes brittle over time after being stretched then contracted repeatedly The insulation develops small fractures that open when heated and close when cooled. When open, they allow shorting of coil windings and decrease or eliminate the coil’s ability to function. I would recommend having an expert from YourMechanic come to your location to take a look at your vehicle to properly diagnose your ignition system.

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