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Discussion Starter #1
I've been trying to get a friends 1999 k1500 suburban running. He ran out of gas, then got it running again, but it died the next day, and hasn't started since. He is a chef, and has no mechanical knowledge at all. His b-inlaw, changed the imline fuel filter, and it still would crank and not start. I started looking at it, and verified fuel psi at the schrader valve that feeds the injectors, and that there was indeed spark. So i'm figuring it is either clogged injectors, or the filter in front of the fuel PSI regulator, now here is my problem . The guy(s) I'm hoping will hep me already know what an abortion the new FI systems are on the 350, but for us ford guys, let me explain. To access the injector system sans the throttle body you have to remove this carbon fiber abortion of an intake(upper). Gone are the old set-ups that were so similar to the ford CFI system from back when. SO I removed the upper intake and replaced the fuel presssure regulator, that has screens and gasketsin front of it. There is no line on the FPI it just clips in place behind these gaskets, and screen filter. After reassembling, the truck tried to turn over briefly, then a loud click like a missing ground in the ignition system. When repeatedly tried, noticed smoke coming off the power cable going to the starter. I verified All grounds to the ignition system, and noticed there was gas leaking from the p-side exhaust. My ? to all u actual mechanics who know better than me is, is this a sign that the injectors are clogged and fuel is dumping from the relief on the regulator or did I install the regulator wrong, I swear I didnt take a line off it, and cant find one that I missed, but still having the same issue. Perhaps the GM gods are mocking me, but its annoying the hell out of me, I do all my own work, and have owned imports, as well as dodges, and all my fords over the years, and never had a issue, I couldnt solve, so any help will be appreciated, and hopefully, I am just missing something stupid.
 

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See if you can at least get it running with some more carb cleaner. If so, its a fuel problem. I had a vortec 350 do something similar to me a while back. Got it narrowed down to either a fuel pump/excessive resistance at fuel pump connector then the customer decided to "fix it themselves" because me installing an acdelco pump costs too much. These things are notorious for burning up the stock pigtails.

I was able to get this suburban to start by just adding some amps with a battery charger, and it would also start on carb cleaner and run great. You have to get more than 60+ psi out of the injector to open the poppet valves. Otherwise, no fuel will drop
-Rob
 

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had a 97gmc 1/2 ton i picked up DIRT cheap { only reason i bought it } that had a simiallar issue . it would crank , carried pressure but not like it should , but enought to make you think it'd run . it would start and fire with starting fluid then run all dain day and give you no issues . turns out ,and this is the reason i got it cheap , the pump has a check ball in it to maintain pressure in it when it's not running . give you three geusses what went bad , the check ball . it was letting the fuel bleed back past it into the tank and no fuel / pressure to fire her up . also seeing as you got fuel running out the exhaust maybe you got fuel injectors that are stuck open ??? again crazy but have seen it .............
 

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Discussion Starter #5
Do you mean leaking out of the exhaust, or just by the exhaust?
I mean leaking from the exhaust where the system bolts to the manifold, I pulled the second plug on the p-side,(2nd from the front of motor) and gas poured out, not so with the other plugs
 

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Discussion Starter #6
had a 97gmc 1/2 ton i picked up DIRT cheap { only reason i bought it } that had a simiallar issue . it would crank , carried pressure but not like it should , but enought to make you think it'd run . it would start and fire with starting fluid then run all dain day and give you no issues . turns out ,and this is the reason i got it cheap , the pump has a check ball in it to maintain pressure in it when it's not running . give you three geusses what went bad , the check ball . it was letting the fuel bleed back past it into the tank and no fuel / pressure to fire her up . also seeing as you got fuel running out the exhaust maybe you got fuel injectors that are stuck open ??? again crazy but have seen it .............
When I tried starting fluid, the closest I could get to getting it running was allot of fireback through the tb, I was hoping that it would fire w/ the starting fluid, amd pull through any thing clogging the system with the vacuum that a running motor would pull, but no luck. Fuel injector stuck sounds possible, as I said it is dumping fuel. I noticed on the manifold one of the connectors I had to pull when removing it was hooked to a sensor marked as pressure 5volt ground interupt. Am I correct in thinking that this is to cut off theignition system if it see's too much psi, or not enough? or is it a safety that kicks in if your filling the area between the manifolds wiyh fuel. Thanks in advance and to all that have replied so far
 

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I noticed on the manifold one of the connectors I had to pull when removing it was hooked to a sensor marked as pressure 5volt ground interupt.
I believe you are talking about the MAP sensor. it has 3 wires: 5v, gnd, signal. It sticks into the plastic plenum on the passenger side. I would presume that this would not cause a singe injector to dump fuel.
-Rob
 

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Discussion Starter #9
But what would cause the interupt in the ignition. I get nothing but a hard click, and I've checked the grounds over and over, battery is fully charged, and it tried briefly after I reasssembled it, then started the scenario I just described.
 
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