Mitsubishi Repair: 98 montero sport check engine light, fuel pressure regulator, montero sport

Question
I have a 98 montero sport LE.  The check engine light read 450 which was a code saying fuel tank pressure sensor. I replaced the entire fuel assemby which is inside of the tank.  The check light is still on and still reads code 450.  I replaced the fuel pressure regulator, fuel filter, cleaned the fuel system with an expensive additive and upgraded the gasoline, but the light is still on.  The car has a slight hesitation or drop in constant acceleration when I increase speed.  What else could this code be specifically related to?

Answer
Elmer: Did you reset the computer? Could try to recode the car, any AutoZone will do it for free. Could be you don't have something set right. Did you do the work or did you take the car to a shop? If a shop then take it back and let them see what is going on. It could be your computer is messing up too. You need to have that tested. Some computers for your year of car are known to be bad. Or go bad. Hope this helps and good luck!