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Discussion Starter #1
I just had the Pricol electric fuel pressure gauge installed my fuel pressure reads about 8 psi at idle. When at full load or full throttle it drops to 0 psi i asked the diesel parts place and they said the new gauges are like that they are supposed to go down and if they go up to 8psi at full throttle there is something wrong in the full system. So basically they say its backwards from the fuel pressure im used to. Can anyone verify this???

I have and 06 3500
 

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Discussion Starter #3
Yes it does have th eintank pump too
 

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If your fp is dropping to 0 at full throttle you will be needing a lift pump soon.My fp reads around 8-8.5 at idle and drops to like 6-7 at full throttle.My truck has 17k on it now and over time I know it will begin to drop.
 

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Wow...that's low pressure! You will definetly want to look into a lift pump. Even with Smarty and a pressure box, I'm seeing a min of 5psi with stock pump.

Yes, you have it right. At idle you will see the most pressure and at WOT, the WEAK stock lift pump can't keep up with fueling, so pressure drops!
 

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my fp at idle is 7-8 psi and wot i pull it down to 1-2 psi. If i get a stronger pump, how much psi can my cp3 and fuel system take before i run into trouble can i put a pump on that has 20-30 psi at idle and not hurt anything?
 

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my fp at idle is 7-8 psi and wot i pull it down to 1-2 psi. If i get a stronger pump, how much psi can my cp3 and fuel system take before i run into trouble can i put a pump on that has 20-30 psi at idle and not hurt anything?
They can easily take 40+psi, but from what I've read, its best to have lower (around 15psi) at startup...the eliminator fuel system runs 15psi and increases to around 40 with boost...
 

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Discussion Starter #8
The diesel service tried to tell me this was right with the type of pricol gauges because it doesnt have and isolator. So when its at full throttle its supposed to be at 0 cuz it actually regulates something with the flow
 

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That doesn't sound right. Maybe cause its electric? My manual isspro reads steady 9-10 and with my Edge set on hot its drops to about 4-5psi. I also have a pancake isolater inline.
 

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The diesel service tried to tell me this was right with the type of pricol gauges because it doesnt have and isolator. So when its at full throttle its supposed to be at 0 cuz it actually regulates something with the flow
Where'd you/they install it? Mine electric and like I said, I'm seeing a minimum of 5psi.
 

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my gauge read 8 psi and dropped to 1 or so until I installed the FASS 95. Now it runs 12 psi or so and I cant get it to drop below 10 psi.
 

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Discussion Starter #12
Ok im new to the diesel stuff what exactly does a fass do and can anyone explain??
 
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