My 1991 Toyota Pickup has been giving me problems with acceleration. After driving for about 15 minutes, I will lose about 50 percent of my power on the gas pedal. It still idles normal, but it's slow to speed up. This means I really have to push each gear to get up to speed. I am getting engine code 52. Before I knew how to check the code, I replaced the fuel pump and filter, thinking that was the issue. Earlier this summer it had been dying randomly while I was driving. I assumed that replacing a fuel pump and filter would give me results because they had never been done to my knowledge. Unfortunately I still have the problem. It is still throwing the code, and having the acceleration problem. The code is always gone after turning the truck on and off, but comes back after 10-15 minutes. What should I consider replacing, or look into further? I'm handy enough to do a fuel pump, but that's pretty much my limit. It is a 1991 pickup sr5 manual 3vze with 205k miles.