perlubie

I have fitted a replacement motor 3S-FE to my rav4 6 months back and now the car is hard to start sometimes. I changed to fuel filter over a few months back and had to cut the fuel in line to get the old filter out. Some symptoms is the other day I drove the car home from town at 100ks/hour fine then all of a sudden the power dropped off and I could only get 45 ks/hour from it. I also noticed yesterday that the car idleing in the garage at normal idle then for some reason the revs built up to 1500rpm for no reason. Can anyone out there help me or tell me what to look for. I plan on pulling the fuel pump out of the tank today to see if there is anything wrong there.