My Mighty Max gets about 16 miles to the gallon. Just wondering if this is normal or what? No real aftermarket performace parts installed.......  

what year? what kind of driving? that sounds terrible hahaha  

lol i knw i thought it would be better than that. its a 92.....well my driving well i drive fast (when thers open road   ) but usually its bout speedlimit. i guess u could say average minitrucking driving style. what could cause this???  

if you got a Haynes or Chilton manual for your truck. there should be in chapter 00-0 in the front a trouble shooting section and it will list out what it could be. this is if you do not have trouble codes popping up.  telling you what it is. i would think it was the o2 sensors or sensor or a tune up needed plugs wires and cap rotor if needed.  are the most common.  could be the ex-stream of leaking injectors ???? which i do not  think it is.  best thing to do would be check the book like if it says emission system fault read about each component and find out what could cause it and test them. for being broken.