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96 12 valve wont idle, gray smoke

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  #1  
Old 10-04-2010, 11:51 AM
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Default 96 12 valve wont idle, gray smoke

Ok it was pretty cold (39, not bad but colder than it has been) so I went out to start the truck to let it warm up for about 10 minutes before I left for class. I had been inside about 5 minutes, when I heard the truck start making noise. I go out side and it is making a HORRIBLE loud, stomach turning, screeching noise and is starting to sputter and try to die, so I race to the truck and immediately kill it.

I check under the hood for anything that looks out of order, nothing looks bad. Try to start it up, and I have to pump the throttle to get it to even start. I have to give it throttle to keep it running, and its putting out quite a bit of gray smoke, and sounds like it has a really bad miss, but will still rev up a little bit.

I get back from class a couple of hours later, and it's even harder to start, and will barely run over idle speed, even with the pedal mashed, still sounds like its missing really, really bad.

I need some help guys. I haven't even had this thing running a month now and it appears I'm already having problems with it.... really sick right now. The past month and 1000 miles or so I have put on it have been flawless, not even a hiccup.
 
  #2  
Old 10-04-2010, 12:02 PM
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Default Re: 96 12 valve wont idle, gray smoke

Not sure about the screeching, but timing slipped or bad injector would be my first thoughts for the smoke and no idle/no power.

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Old 10-04-2010, 05:03 PM
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x2 i would say check your timing and then the injectors
 
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Old 10-04-2010, 06:31 PM
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Ok it won't even start now. How would I go about checking the timing and injectors? The timing I'm sure I could find a thread on, but I don't remember seeing anything about checking the injectors.

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Ok if I am just turning the engine over, it just sits there and turns over, but if I floor the throttle while its turning over, it will just BARELY try to start. No smoke now, maybe just a tiny bit. Makes me think its not getting any fuel but the screeching noise really scared the crap out of me earlier, I don't know how the fuel system would cause that.

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Another update. Won't even try to start no matter how much throttle I give it. NO smoke either. Sounds like I'm not getting fuel, also if you noticed, how it runs was getting steadily worse.

Cracked the screw on top of my fuel filter, and it went pshhhhhhhhhht.... air. Guess I'll check my lines, may get a jug of diesel and run a line from my pump to it and see if it fixes it.

The screeching still confuses me but I guess it had to be a belt. Didn't sound like it, but I really hope that is all it was.
 

Last edited by EasternAggie; 10-04-2010 at 06:31 PM. Reason: Automerged Doublepost
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Old 10-04-2010, 06:39 PM
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I wonder if the screeching was air sucking into the fuel system somewhere
 
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Old 10-04-2010, 07:19 PM
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Originally Posted by tiremann9669
I wonder if the screeching was air sucking into the fuel system somewhere
Idk that may be a possibility

Well I unhooked the supply fuel line and ran a 3/8" fuel line from a gallon of diesel up to where I unhooked it. Primed the crap out of it, tried to start it, nothing. Primed and primed again, tried to start nothing. Repeated two more times, still nothing. At the end, when I pulled the line out of the jug, fuel ran out of it, so its at least trying to pull fuel there.

I'm startin to wonder if the fuel filter might have something to do with it so I'm gonna go pick one up probably tomorrow, but won't get to change it til Wednesday most likely.

What do yall guys think?
 
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Old 10-04-2010, 07:46 PM
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Sounds like a gelled up fuel filter. The screeching is a wildcard though
 
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Old 10-04-2010, 09:42 PM
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I wouldn't be gelled at 39 degrees, where did you unhook the line, it could possibly be bad between there and the pump? Just because it pulled some fuel out of the jug dosn't mean you had enough fp to run, best way to know that for sure is with a guage. You could crack open a injector line while someone else is cranking it, if you don't get a pretty good spray of fuel when you crack it then you know it's a fp problem.
 
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Old 10-04-2010, 10:45 PM
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Originally Posted by tiremann9669
I wouldn't be gelled at 39 degrees, where did you unhook the line, it could possibly be bad between there and the pump? Just because it pulled some fuel out of the jug dosn't mean you had enough fp to run, best way to know that for sure is with a guage. You could crack open a injector line while someone else is cranking it, if you don't get a pretty good spray of fuel when you crack it then you know it's a fp problem.
Yeah I'm going to change the fuel filter first thing. Then I'm going to check a couple of lines. One of my friends that has a 12 valve had the same problem, it was sucking air. One of his hoses had dry rotted, the one that runs between the fuel heater and lift pump, and mine doesn't look to be in much better shape.

And I'll try the injector method. I'll keep yall posted. Thanks for all the help guys and keep rolling the knowledge in, every bit helps
 
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Old 10-04-2010, 10:47 PM
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priming the 12 valve is one of the most next to impossible feats i've been against next to bleeding the clutch hydraulics.

crack them all, when fuel starts shooting all over hell from all of them, tighten them one by one while cranking.
 


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