I have a 98 Suburban, 5.7L. The engine starts and dies. Fuel pressure constant at 70 lbs. No trouble codes present. I hooked a node light to the injector harness. When starting the injectors fire normally. I can sustain idle with starter fluid. When sustaining the idle the injectors only fire intermittently. These symptoms cause the vehicle to start and then immediatly die. What could be causing the injectos to stop firing or fire only ittermittently after starting?

 

Turn they key to the on position....is the security light flashing?If so, leave the key on for another 10mins, untill the light stops flashing. Turn key off, then start engine

 

Thanks for your response. I'm gonna check it out. I have had some problems with the security system.

 

I tried that thing with the security system but it's still cutting out. The darn thing wants to run. Anybody know how I can disable the security system so I can eliminate that as the source of the problem?

 

does the light flash when the key is on?

 

The security light flashes for about 3 seconds when the ignition is first turned to "on" and then it stops.

 

If the light doesn't flash, then we're not looking at a passlock issue. Its most likely either a crank sensor, ignition module, or ecm