I have a '97 Chevy Suburban K1500 with a 5.7L Vortec. I did some engine work over a week ago on this truck. What I had done is disconnected the battery for starters. Computer was offline for 3 days. I unplugged the crank sensor from the timing chain cover and removed the cover. Timing chain and gears were not touched and reluctor wheel was left in place. I raised the engine up and dropped the oil pan and replaced the oil pump. I had low oil pressure, so pump needed replaced. Simple. After installation of the new pump, the pan(with new gaskets) and timing cover were reinstalled. After that, the oil filter re-locator and starter were reinstalled. The crank sensor was plugged back in and battery hooked back up. It cranks but no fire. New crank sensor was installed but nothing. Grounds were cleaned and checked. All ignition parts were taken to Napa and all tested good. This includes the crank sensor, cam sensor, ignition coil and pick up, distributor and pick up in it, cap, rotor, every thing! Even has the mechanic stuck! Far as I can tell I didn't pull or strain any wires just by lifting the engine. I really need help on this one! Just a bit in over my head with this! Thanks every one in advance!!!