97 Chevy 1500 5.7L Vortex will not start after changing fuel filter and pump.?

My truck started to start hard. Then it got to the point where I needed to prime the throttle body with gas to start. After a day, I would need to prime again. Then it would not start at all. I changed the fuel filter and now the fuel pump with the same problem. I find the spark from the coil wire is very weak and yellow/orange in color. Any clues?|||you may need to replace the coil or check the grounding points on your engine|||Most likely the fuel metering valve has went out. It is located under the upper intake (plenum). Rather expensive common problem, part list is around $400.|||if spark is orange, that is a sign of a weak spark or a large gap that the coil is trying to bridge. on many of the gm cars, if the computer does not see a spark it will not trigger the injectors. with out spark the computer may not send a signal to the fuel pump relay.