Mazda will not start

Have a Mazda B300 P/U. Has 156000 miles. Just put in a new long block 3.0 ltr engine. Replaced all belts. Hoses, Plugs, Rotor and cap, run it for 2 weeks and had a check engine lite. It was for the o2 sensors. Replaced both. Then had a problem with engine just shutting off as you where driving down the road. Would start right back up as soon as put in netureal and turned starter over, Would go a few miles the do the same. So to try and solve that problem. Replaced Ignition Module, Coil. Checked timing, good. Checked fuel psi. It's 38 lbs. Checked injectors for pulse, Compression is all good. Everything is there for it to run but the engine still willl not start, Turns over but will not run. Have ran out of clues.