94 YJ 2.5L. About 40k on new motor. Sporadically will NOT start. Turns over fine, fuel at rail at proper pressure, compression good on all 4 cyl. New coil, plugs, wires, distributer, coil pickup, correct voltage to coil from ecm when cranking. Checked sensor in bell housing, passes chilton's manual test. When it runs, it is perfect (for a 2.5 anyhow). I went to leave work, turned over but wouldn't start. Walked home, got truck, returned to work to pick up stuff (maybe 15 minutes later), just for hell of it, tried the key and the jeep started right up. Can't duplicate when it is at garage, have had 3 different mechanics work on it, no codes on computer. Completely random, has done it when dry, wet, hot, cold, etc. No pattern that I can find.