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Discussion Starter #62
That’s plugged? Looks like a relief valve.
I’m pretty sure it’s one of the higher pressure relief valves, i just took a glance maybe it’s not.
You know what that alligator part is.
Btw when I popped the hood and stuck my head in there their was a diesel smell
 

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It could be a solid block plug on the relief that allows you to screw the line back in just it's not just sitting there. Remove it and double check. If it's not, there's a few companies out there that make a fuel rail plug and then do some testing.
 

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Discussion Starter #65
It’s making max boost, filter is fine
The fuel pressure is lower than the desired,
Minimum actual-50
Minimum desired-49
Average actual-96
Average desired-100
Maximum actual-180
Maximum desired-181
Half throttle it is about 20mpa below where it should be
Rail pressure chart attached.
908697
 

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Discussion Starter #66
It could be a solid block plug on the relief that allows you to screw the line back in just it's not just sitting there. Remove it and double check. If it's not, there's a few companies out there that make a fuel rail plug and then do some testing.
That’s what it appears to be, it’s larger than stock so that is what I think it is, Do you know what that alligator part is?
 

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It looks like someone didn't hook the fuel system up right and used a threaded bridge to make the connection. I'm not sure thought. It does look odd.
 

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Looks like a stock fuel bowl delete, but hadn't seen one like that before.

The PRV and PRV Delete look identical. Only way you can tell is to remove the bolt and see if it's solid or has the allen head plug.
 

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Discussion Starter #70
Looks like a stock fuel bowl delete, but hadn't seen one like that before.

The PRV and PRV Delete look identical. Only way you can tell is to remove the bolt and see if it's solid or has the allen head plug.
This truck is such a mystery to me it’s not even funny, I personally don’t feel like messing with things that have anything to do with “high pressure” so I’m planning on bringing it to the shop
 

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PRV doesn't even need tested that way though. You could do that yourself. Connect HPTuners to the truck to monitor rail pressure. Unplug the FCA and start the truck. If it can't hold 26.1K steady, PRV is likely to blame.
 

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Discussion Starter #72
PRV doesn't even need tested that way though. You could do that yourself. Connect HPTuners to the truck to monitor rail pressure. Unplug the FCA and start the truck. If it can't hold 26.1K steady, PRV is likely to blame.
I’m not on HP I’m on EFI live and can’t figure out how to get to rail pressure, also where’s the fca plug
 

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I’m not on HP I’m on EFI live and can’t figure out how to get to rail pressure, also where’s the fca plug
Yeah realize that from the screen shot now, how did you get that screenshot showing rail pressure?

On the back of the CP3. Should be the only electrical plug. Towards the drives side.
 

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Discussion Starter #74
Yeah realize that from the screen shot now, how did you get that screenshot showing rail pressure?

On the back of the CP3. Should be the only electrical plug. Towards the drives side.
Mat sent it to me, I just got mine to work, pushed some buttons and it works. You say unplug it, data log it and then see if it holds 26?
 

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Mat sent it to me, I just got mine to work, pushed some buttons and it works. You say unplug it, data log it and then see if it holds 26?
Yeah, just don't run the truck long like that. If the PRV is bad you'll see the pressure bounce.
 

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Discussion Starter #78
I started it it spiked to 26 then it fell to 18 then spiked to 26 and held till I shut it off
 

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PRV doesn't even need tested that way though. You could do that yourself. Connect HPTuners to the truck to monitor rail pressure. Unplug the FCA and start the truck. If it can't hold 26.1K steady, PRV is likely to blame.
What’s the theory behind that being the test for the prv? If the cp3 was weak couldn’t it maybe make it to 26 and then drop off? Or would it be more likely to hold then drop when load is applied?
 

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Discussion Starter #80
What’s the theory behind that being the test for the prv? If the cp3 was weak couldn’t it maybe make it to 26 and then drop off? Or would it be more likely to hold then drop when load is applied?
I would think that if the cp3 was bad you wouldn’t make the 26,000 or it wouldn’t hold, or the prv wouldn’t blow off as well. If The truck makes 26000 steady wouldn’t that mean that there isn’t a fuel issue because it holds 26 steady?
 
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