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Engine woes or fueling issues?

Old Sep 1, 2022 | 10:40 PM
  #21  
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I will tomorrow as soon as I get home from work. I am getting off early so that helps.
I was also thinking maybe smoke test the intake and see what I come up with. Possible vacuum leak?


Or maybe I just buy the single cab I have been looking at and park the truck for now. Would be a nice little problem solver right there.
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Old Sep 2, 2022 | 08:36 AM
  #22  
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Let me put the idea of a leaky injector into your head. If so, it leaks down in the off cycle and you lose pressure so that the truck won't start until the pressure builds again. And it runs rich because one injector is stuck open.
Just hook up your pressure gauge and watch how fast the pressure drops after you turn the engine off to test.
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Old Sep 2, 2022 | 09:28 AM
  #23  
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That's kind of funny because that makes some sense and is the opposite of what I had when I installed the engine. When I installed this engine I had 2 stuck closed injectors with no codes, truck ran like crap and obviously ran lean but no codes.

Do you know what the factory says should be the wait until pressure drops? And how it is supposed to drop?
I remember with a snap-on scan tool I can test each injector for pressure with the key on engine off. I may be able to get ahold of an Autel scanner that should be able to do this test. Would that suffice as well?
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Old Sep 2, 2022 | 10:29 AM
  #24  
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I guess I could pull the fuel rail off and turn the key on and see if any fuel comes out of the injectors, that should show a stuck open injector pretty quick.

anyone have an issue with that?
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Old Sep 2, 2022 | 07:52 PM
  #25  
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Did an injector balance test and my results were basically 55psi down to 30psi on every cylinder.

That seems really low but I am not sure.
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Old Sep 2, 2022 | 09:01 PM
  #26  
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Nice and wet. Personally they smell somewhat like a mix of oil and gas. I don't know, my nose I guess may not be calibrated.

This kind of leads me back to thinking pressure regulator again. Also I had the pressure gauge hooked up for about an hour and it only dropped down to about 40 PSI in that time.
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Old Sep 2, 2022 | 09:51 PM
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How is throttle body looking? Iac passage and all.
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Old Sep 2, 2022 | 10:01 PM
  #28  
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To me it looked clean. Well that is subjective, it was dirty but nothing out of the ordinary I thought.
I can pull all that apart and spray down the MAF and the throttle body will cleaner tomorrow.
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Old Sep 2, 2022 | 10:04 PM
  #29  
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Originally Posted by shakenfake
To me it looked clean. Well that is subjective, it was dirty but nothing out of the ordinary I thought.
I can pull all that apart and spray down the MAF and the throttle body will cleaner tomorrow.
Stop messing with the MAF. You are more likely to contaminate it.

Look in the IAC passage. Pull the IAC valve out and check to see if its gummed up.
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Old Sep 2, 2022 | 11:54 PM
  #30  
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Get that wideband working mister
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