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FP Changing Sporadically At Idle

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  #21  
Old 05-07-2008, 10:29 AM
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will do
 
  #22  
Old 05-10-2008, 12:46 PM
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I fixed the straw, i put a slashed cut into it, before it was straight.

i think there might be air in my t-tap where my FP sensor is i cant get a solid reading. itl climb up to about 14 very slowly and then drop down to 10.

its getting more pressure than before but ima add a bleeder valve so my FP gauge can read better.


Straw looks like the attachment now.
 
Attached Thumbnails FP Changing Sporadically At Idle-draw-tube.jpg  
  #23  
Old 05-10-2008, 05:38 PM
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Also once it climbs up to 14 psi there is a groan coming from the system.

I really cant pin point it but im going to add a bleeder to my FP gauge first and see how it turns out

---AutoMerged DoublePost---

checked all lines and fitting no leaks and no air leaks, isolated my FP gauge and it still wont hold anything over 11psi

What is going on here
 

Last edited by 2500HeavyDuty; 05-10-2008 at 05:38 PM. Reason: Automerged Doublepost
  #24  
Old 05-11-2008, 10:51 AM
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There are a few things that could be causing the low and sparatic fuel pressure. One is that your draw straw is cut too short, if you cut it at an angle you want the lowest part of the sraw straw to touch the bottom of the tank, and a 22.5* angle works better than a 45* angle. Also, have you checked all the lines and make sure that one has not gotten pinched or kinked?
 
  #25  
Old 05-11-2008, 11:32 AM
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Originally Posted by 06 DIESEL
There are a few things that could be causing the low and sparatic fuel pressure. One is that your draw straw is cut too short, if you cut it at an angle you want the lowest part of the sraw straw to touch the bottom of the tank, and a 22.5* angle works better than a 45* angle. Also, have you checked all the lines and make sure that one has not gotten pinched or kinked?
The lowest point on my draw straw is about 1/8 from the bottom of the tank.

I checked all the lines airdog shorted me on the fittings so i used alot of line for my fuel return line and it makes it own path when it turns on. It bends but it doesent kink in any way.

I went down and observed my pump while its running before startup and when it hits 14 psi i hear bubbles being made inside my tank and my pump makes a click and skips.

It does get tight around my FP tap, but there is only about 8 inches of hose to play with and my T-Tap is about 6 inches long. lines aren't kinked they just bend a little cause that area is tight.
 
  #26  
Old 05-11-2008, 07:58 PM
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The noise you hear in your tank is the fuel returning to the tank that is not needed. My 100 shows 17# all day long, basically until I am out of fuel. Do you have any pictures of how tight your FP tap and line is?
 
  #27  
Old 05-11-2008, 08:05 PM
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i will get some right now. its not bad, but i have to remove the inner fender liner and cold side IC tube to mess with it.

Well it makes about 14 psi and then i hear a thunk coming from the tank, which could be the fuel return.

after it drops it hits 10-9 psi.

on the road i hit 11 psi consistently. an under WOT it drops down to 3 psi if i lay on it for a while

brb
 
  #28  
Old 05-11-2008, 08:20 PM
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Ok, the FICM is on the right os the Tee and Filter is on the Left of the Tee.
 
Attached Thumbnails FP Changing Sporadically At Idle-img00293.jpg   FP Changing Sporadically At Idle-img00292.jpg  
  #29  
Old 05-11-2008, 09:23 PM
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It sounds like to me you have something wrong with your pump. Mine will hold 17# all the time, even under WOT. I would give Charlie a call and see if he has any other suggestions.
 
  #30  
Old 05-11-2008, 09:35 PM
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i plan on doing that tomorrow. its hard for me to get anything done though during the week. and lots of things to do
 


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