Red3.slow

Well I hate to say this because my 3.0 has been one of the few I've known never to not give me an ounce of trouble but now its starting to act up on me.

-216,xxx miles
-Head gaskets replaced, but with out ever have failed, about 60k ago
-CEL on for EGR
-No cat
-Don't know the last time O2 sensor was replaced
-cap and rotor replaced about 8 months ago
-wires replaced about 18 months ago
-spark plugs changed about 5k ago
-Oil changed regularly although i need to do it soon

Now to my actual problem!

over the last few week my mileage has dropped almost 75 miles a tank to only about 165 miles a tank. It also feels more gutless than usual and doesn't want to get up above about 70 miles per hour on the interstate.

Oh and the motor doesn't want to rev to about 4k and will hardly go above that.

I'm open to any suggestions