Can't get it to start.

OK, so the old motor for the 2002 prism a 1.8, threw a rod. so found another 1.8 in a 2001 corolla. had to swap valve covers to use the C.O.P's. they all spark, although a little yellow. swapped the throttle body, the new 2001 had and extra sensor??, checked and replaced some fuses, changed out a suspect relay. the only difference remaining is the oil pressure control (timing) near the #1 cyc. the 2001 has a boss for this but is not milled. read, everything I could about this and, and of course everyone cop's out because it's a different year. but it's still a 1.8 almost identical. I heard this motor run before I bought it, only has 40K, still can't find any new leads or things to check next.   HELP