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1995 4.3l V6 Vortec SPUTTERING/MISFIRE on acceleration

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  #11  
Old 05-24-2012, 12:56 AM
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Sounds like you got it covered. Its either the fuel pressure regulator or you have a leaking injectors. With that much of a drop I would suspect the regulator. Time to pull the plenum. It should be black and sooty, it its clean you know something is leaking. At that time you can test the regulator to determine if its the reg or injectors.
 
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Old 05-24-2012, 01:29 AM
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Originally Posted by 50lb_cat
Sounds like you got it covered. Its either the fuel pressure regulator or you have a leaking injectors. With that much of a drop I would suspect the regulator. Time to pull the plenum. It should be black and sooty, it its clean you know something is leaking. At that time you can test the regulator to determine if its the reg or injectors.


Is the regulator part of the spider? If I buy a new one would I just get the whole setup? Do you think that the fuel pump has anything to do with it?
 
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Old 05-24-2012, 10:56 AM
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The reg. Is a different part from the spider. From the numbers the fuel pump is ok. If you want to change both the reg and spider I would reccommend getting a delphi MFI conversion from rockauto, they are less prone to failure.
 
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Old 05-24-2012, 10:57 AM
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The reg. Is a different part from the spider. From the numbers the fuel pump is ok. If you want to change both the reg and spider I would reccommend getting a delphi MFI conversion from rockauto, they are less prone to failure.
 
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Old 05-24-2012, 11:27 AM
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so the problem is most likely that? Anything else that could be wrong?
 
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Old 05-24-2012, 11:41 AM
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Sorry about the double post, damn android phone lol. Your key on pressure is good so its not the pump. You have fast leakdown and that usally points to the regulator. Look down the throttle body, if the passenger side is very clean or shows signs of washing then that confirms it.
 
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Old 05-24-2012, 09:01 PM
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i looked into the engine and both sides seem the same. it does look pretty clean though... like silver splotches
 
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Old 05-24-2012, 10:47 PM
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Take the plenum off so you can pinpoint the leak, but that's definetly where the leak is coming from.
 
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Old 05-24-2012, 10:48 PM
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I was trying out a few things today with the fuel pressure gauge, and it has gotten very severe with acceleration. My fuel pressure however stays consistent, until the engine dies and the key is still in the ON position, then the pressure bleeds out pretty quick. When I was driving it the engine seemed to be gasping right before it died, or when the RPM would drop super low like 500 then jump back up to 1500 (this is while idling in drive). Like a said before the inside of the intake manifold looks pretty clean, and it was more moist than before. I think I'll just replace the injector and pressure regulator. Anybody know what MFI conversion would work with the 1995 GMC jimmy 4.3l vortec v6 engine?
 
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Old 05-24-2012, 10:52 PM
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Originally Posted by 50lb_cat
Take the plenum off so you can pinpoint the leak, but that's definetly where the leak is coming from.
I saw this after I posted, I'll do that and make sure that it is there.
 


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