1990 Buick Regal LTD, 3.1 Litre Multi porte engine. Starts for a few seconds and stops. If I keep cranking the motor it does try to start but won't guite run. If I squirt gas into the throttle body while someone tries starting it, it starts right up and runs fine untill I quit feeding it gas manually. Replaced fuel pump, filter, TBS, intake plenum gaskets, EGR gasket, throttle body gasket, Fuel pressure under hood 70 psi, rail pressure 45 psi, new PCV valve, and also cleaned all grounds. If I put a node light on an injector when someone tries to start it, the light is real bright for a few seconds and then turns real dim and stays dim till cranking is stopped. It has started twice on it's own without spraying in gas twice and idled for a minute once until I touched the gas, second time it run for ten minutes, I could rev it up to about 1200 RPM quite a few times till I went for higher RPM and it just died and would not restart again. Any suggestions as to what the problem could be?"