Texcuda
I'm Awesome
IIRC Passlock cuts power to the injectors on these trucks, not the pump. I'm betting this is a Passlock issue.
Hmm, interesting. The forum posts I saw specifically state that Passlock shuts off the fuel pump, not the injectors, thus why I hot wired the fuel pump. The security light on the dash did not flash at all either, and it seems if the problem is Passlock related, the security light is supposed to flash at least a few times.Yup it sounds like a Passlock issue to me too. It cuts power to the injectors, and the only way to get rid of it is to have it deleted in the PCM by a tuner.
In that same vein, shouldn't I be able to keep it running on carb cleaner or gas poured directly into the throttle body, if the injectors are being shut off by the pcm?
It has a brand new fuel pump and has 60 psi: key on, engine off; 52+ during initial crank and the 1 - 2 second run time.Can you hear the fuel pump prime? Is the fuel relay engaging?
I may just spring for HPTuners as we've been talking about having the rear 02's tuned out and I can make some other changes as well.You can bypass it, but the only way to eliminate it 100% is to disable it in the tune as @HotWheelsBurban mentioned. Everything else (including the resistor bypass in that South Main Auto YouTube vid) is just fooling the system into thinking it's operating properly. If another part of the system fails (like the module itself) the truck won't start again.
Disabling it in the tune will prevent the PCM from looking for a signal from the Passlock module permanently. Being a '98, the PCM is supported by HPTuners and EFILive so it shouldn't be too hard to find a tuner who can do it.
Thanks for the info. Your truck's symptoms seem to match my son's exactly.Believe me, I tried everything with my '99 Burb when this happened. The truck would be fine, start every time for a week, and then you'd try to start it again and it wouldn't do anything. Just run for a few seconds and then quit. And keep doing that....
And of course when you really needed to get somewhere (like say, get to work on time) that's when it was most likely to act up.
So I googled the problem, and came up with this forum. And they told me the only sure thing was to get the PCM delete.....
So I did that, and no more problems.
Gentleman, I truly appreciate the info and will report back with what I find. I'll start looking into HPTuners now as well.
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