Bought a non running 740 a few months ago and after redoing nearly the whole fuel system the car runs and drives. On start-up I have to press the throttle and keep it at 2k rpms for 20 seconds. When I slowly come off the throttle, it will idle down and nearly stall before coming up to 1000-1200 rpms and continue to do that until I put it in gear where it will sit at 750 nicely. When in gear and accelerating it will hesitate between 2-3k rpms and after 3 runs smooth and makes good power. When hesitating it may missfire once or repeatedly before reving nicly past 3k. I have cleaned the Idle Air Control valve and it buzzes w/ the key in position 2 indicating it is likely working. Unplugging the IAC causes the engine to rev high at like 1500 rpms. Have no vacuum leaks, smoked tested to figure out. Timing of crank and cam is correct, balencer wheel has slipped but made new marks with TDC and set timing to 12 degrees BTDC at 750 rpms. New bocsh OEM high pressure pump and makes correct fuel pressure. Injectors have been checked for flow and tested good. Im suspecting potentially the MAF. I have a new aftermarket one I put in trying to solve the no start which made no change, may swap back in the old OEM one.