1997 yukon no start

[boosted s10]

I have a 1997 gmc yukon 5.7 4wd. First my fuel pump went out so i replaced that. then i had a code for cylinder 5 misfire so i replace spark plugs, cap, rotor,and pcm and wires still misfired, so i replaced the intake gasket and cylinder no. 5 injector, misfire went away. Then i had a problem with it wanting to quit or it hitting fuel cut when you pushed on the gas pedal, chenger the fuel filter it was a little better, then i cleaned the mass air flow and it ran perfect, shut the truck off, then went to go take it for a ride, got about 5 blocks and it shut off on me, took about 30 sec. and it restarted but ran like it did before, so i got it home and it quit again, so i restarted it again and got it in the driveway. so i went and bought a raman. mass air flow put it in and still no start, went and got 3 mass air flows still no start, have checked all connections all get power, and all grounds are good, truck gets fuel up to the injectors but injectors do no turn on. If i spray starting fluid it starts then dies. For some reason the injectors will not turn on. I have also tried to replace the crank shaft position sensor. Any one any ideas on what to check any help would be great. I have good fuel pressure also. thanks for your time!

[ronaldk]

check tp sensor for 5v on grey wire, blk to ground and drk blue is ref to ecm at idle position apx .5volts full throttle apx 4.5 volts.Throttle position sensor tells ecm amt of fuel to be released by injectors.

[maxwedge]

How about checking fuel pressure, 65 psi.

[boosted s10]

the fuel pressure is alot lower than 65psi i checked it at the port right before the fuel injectors would that stop the fuel injectors from turning on and what do you think bad fuel pump?

[maxwedge]

It will not stop them electronically but 65 is needed to pop them, you need to confirm injector pulse to be sure.

[boosted s10]

Yea they have power and they pulse but they will not let any full into the engine. So what your saying is they will not spray unless there is 65 psi there? thanks alot for all your help i really appreciate it.

[maxwedge]

I haven't seen the results of 60 psi, but 55 will not work for sure.