Injectors won't spray.

[CandyMan337]

I've got a 95 yukon. I can't get it to start. after spending $100's of dollar changing almost everything you could think of under the hood it Still won't start. I've replaced the:
1) map sensor
2) ignition coil
3) idol air control
4) throttle position sensor
5) fuel regulator
6) injectors
7) injector connecters
8) fuel filter
9) engine control computer
The fuel pump, & distributor, cap, & rotor are only 2 months old. We have traced the fuel all the way up to the injectors, but they just won't spray any fuel. We've checked the wires on the connectors & they ARE getting power. I'm lost at this point & very aggravated not to mention broke after all the parts. Any help would be greatly appreciated.

 

[Gzes]

Have you tested the injectors themselves? Pull them off get junkyard pig tails a switch and 12 volt battery and see if it sprays

 

[CandyMan337]

No I haven't tried that. But I'm bout to go outside & try it in a few mins. Thx

 

[SunlitComet]

you need to do a burst of power to them for about 1 second each at a time and have your fuel pump running.

 

[CandyMan337]

I just tried it. Still not spraying. You can hear the injectors click but still no fuel coming out. I'm wondering if the fuel pump is pushing out enough pressure. I guess that would be the next step to test.

 

[Atomic]

If the fuel pump was pushing out ANY pressure fuel would spray.

Are you sure there is gas in the tank? New fuel pump? Did you use the right hose? Filter clogged?

Put a fuel pressure gauge on the rail and test the pressure there with the pump on.

 

[SunlitComet]

if you test the pressure output you should get about 13-15 psi.

 

[CandyMan337]

Thx for trying to help guys. I finally broke down & took it to another shop. After 2 days of them tracing & trying all of the same things I did, they had to call the dealership. It ended up being another sensor that's on the back of the distributer cap. Not sure of the exact name of it but they said it controls the pulse to make the injectors fire & spray. I hope this can help someone save some time & money in the future.

 

[SunlitComet]

ignition control module. does not fire injectors directly tho those are handled by the pcm. it was likely the "c" terminal on the module that did not have a reference signal any more if the module was really at fault. hope they used thermal grease on it.