Help me out guys!

I've been getting bad gas mileage (approx. 16-17 city and 22 hwy) and just the other day a DTC code popped up, I got it scanned and it was:

P0108 Manifold Absolute Pressure (MAP) Sensor Circuit High Voltage

Could it be a faulty MAP sensor, and should I replace the MAP sensor, do you guys think that would help, or if not what else could it maybe be?

Either a bad MAP sensor or your vacuum is messed up (vacuum leak or whatever). Had any problems with your car besides gas mileage? Like maybe running rough at idle or missing? Usually a bad MAP sensor will lead to those problems as well.

If the idle is rough or unstable, you need to correct that first. With the engine idling, MAP value on a scan tool should read 3.5 Volts.
Could be a bad MAP sensor, plugged or restricted vacuum source, (check the PCV Valve, since it's under the MAP sensor), or bad connections at the MAP Sensor or PCM.

Nope, no problems at idle except for tiny little "hiccups" that occur occasionally, that are barely even noticeable. I think that would be cured by swapping the fuel filter.

But just the code, that's it, no really ill side effects that I can tell, with the exception of poor economy.

I have been going easy on it, but the mileage I am getting is like I've been on it all the time... I dunno, I'll maybe try swapping the MAP sensor and PCV valve, and see if that helps.

16-17 city MPG is bad for you?... i average that.

When you're swapping the MAP sensor, look inside the connector, and make sure the terminals haven't backed out. And the PCV Valve should have an O-ring on it. Clear the code, and road test it; shut the car off twice for at least 2 minutes, and keep us posted.