The motor seems to be running smoothly on the flats or downhill, but as soon as get near higher rpm's and definitely on hills it tends to bog down and start immediately losing speed. Almost as if the motor is bogging down.

 

Is this more of a symptom of a bad fuel pump or is it possibly a tranny issue??

 

when did you do your last tune up, plugs, wires, coil packs.?

 

possible plugged cat converter

 

I agree with mayhem on possible plugged cat.

 

Can you get hold of a scan tool at the local auto parts' store? (I heard they will scan for free although I'd buy something anyway or tip the guy).