Injectors stop pulsing.
 

hey guys, got a quick question. Now before i get flamed about searching this issue,..... I have and to my surprise, there really isn't anything I've seen that answers this question. What would cause the primaries to only pulse for a few seconds while cranking to start? I've got pulse, which is verified by some LEDs that I've custom built and hard wired to the each injector. I know that the secondaries don't come online till about 3800 RPM with a load but my primaries flash alternately for about 5 seconds then stop. Now, I have done the simplified sequential mod and doctored the harness with 330 ohm resistors as well to avoid the CELs. Im sure I didnt screw anything up with that because she was running fine before my latest rebuild and i was sure not to change any settings like the TPS or the Bleed screw, and stuff like that. Im at a loos. Any ideas would be great. Thanks in advance for your help

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What ECU are you running?
The 5 second on times leads me to believe the primaries are kicking on while cranking/startup but are failing to stayed on/powered after it starts?

Any more info on the setup would help to figure things out.

thanks, forgot to mention, the ECU is stock, injectors are stock, have an aftermarket adjustable FPR but all other systems are stock. oh, have Rotary Aviation OMP adapter and MSD on leadings but i doubt that has anything to do with it. Im beginning to believe that the theft deterrent system has something to do with it. Just a hunch because my Tahoe did the same thing till I bypassed the alarm system. That Vpas system is known to malfunction from time to time. again, just a huntch.

was a bad injector on my secondary rail. weird but once i removed it and tested the system again, all was back to normal. just thought id put it out there for the next guy!