Q: Misfire

asked by on October 10, 2016

what would make a number 2 spark plug have a miss fire..??
My car has an automatic transmission.

The valve cover should be checked first to see if it is leaking oil into the spark plug tubes in the head. The leaking oil that’s getting onto the spark plug wire and plug can cause it to arch to the ground cause the spark to not reach the spark plug.

You should remove the ignition coil over the spark plugs and check to see if oil is on the boots, this would indicate that the valve cover is leaking. Once this is checked, replace valve cover and spark plug tube seals as necessary. Afterwards, clean out the spark plug holes and replace spark plugs and spark plug wire boots. This is the most common problem you will find with the misfire of one or more cylinders.

If you need assistance with this, consider YourMechanic, as one of our mobile technicians can come to your home or office to diagnose the misfire firsthand and make the necessary repairs to your car.

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