Q: I drove my car with 2 spark plugs unplugged misfired horribly, what kind of damage could I have done?

asked by on January 20, 2017

I drove my car a little over an hour with 2 spark plugs unplugged. It misfired horribly. Did I damage the coils? And if so how much would it cost to fix?

My car has 135450 miles.
My car has an automatic transmission.

Hello, This should not have caused any damage and is generally not something to worry about. To the extent you continued to drive it this way, for very long the un-burnt fuel that is pumping through the non-firing cylinders may eventually contaminate the catalytic converter by causing too much raw fuel to be pushed through the exhaust. I would simply reconnect the plug wires and try driving the car again to see how it runs. If the misfire continues, this may be a result of a larger problem that should be looked at by a mechanic such as one from YourMechanic.

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