I have a 1994 4x4 automatic chevy blazer s10 v6. I just got it used obviously but I noticed when I drive it say past 50mph on a sloping incline it seems to have trouble accelerating so I end up having to push the gas pedal all the way down to the floor to keep it at 50mph in a 55mph zone which in turn burns a lot more gas. Yes I put it in 2nd and it still has trouble. Is this just normal for this model or is there something I can do to modify the engine or is there something I might have to fix? I'm stumped. Taking it in for a tune up just in case it's my spark plugs.

 

The symptoms sound like a plugged catalytic converter.