That car is equipped with a lifetime (in theory) air filter. You should read in the owner's manual how to test it, and test it to make sure it's good.
I did start having problems with my spark plugs right around the same time in mileage. If those are the factory plugs, then yes, it could be something due to the plugs. It could also be due to the coil boots- what goes for spark plug wires in these cars that have coil on plug ignition. Both parts can be replaced. Plug boots were about $5-8, and plugs should be about $3 for platinum plugs. I suggest you get Autolite 104PP plugs, that's double platinum plugs, or factory recommended Motorcraft plugs.
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Originally Posted by the user formerly known as ZX3_Chick
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