Gas Mileage Question ?

too many factors can play into this, here's a few:

Make sure your tire pressures are all at factory specs
Check your driving habits
Get an alignment
Are you carrying any more cargo than you used to
be sure all your fluids are changed regularly
Depending on miles, which you've got an 02 so you shouldn't need to, but new spark plug wires could help, but since you're not running high horsepower, you can just replace them with any parts store has as a replacement instead of high dollar plugs.

IslandBlueStang:

This recently happened to me. Get a new fuel filter and or check your plugs/wires. IRT your question about performance wires there are all types out there, with 8.8mm? being very common. MSD, Bosch, Accel are a few brand names. Good luck.

Check your MAF and TB for crud and clean it out. Throw some Fuel Injector cleaner into the gas tank. Change air filter out for a K&N or equivalent.