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howdy guys, so the other day i was lookin at my records on my edge and i was lookin through em and saw that the record low fuel press was 4.....i almost pooped my pants when i saw this. I dont remember seeing this on my edge screen but it verry well could of happend that it got down to 4. Strange thing is that when im idle im sittin at 11 or 12psi and when im driving around its usually 10-8, mabye 7 when i get on it a little. So my question to you guys is, is my lift pump crapping out on me? when i bought it the lift pump was less than a year old... thanks for any help!
 

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My second OEM lift pump didn't even put out more than 6-8 sometimes with a moderate load at freeway speed when new. I bit the bullit and put a Fass 95 on a couple of years back. Now it sometimes dropes to 8-9 on a hard pull and idles about 13.
 

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If it's dropping to 7 or 8 then it's too low anyway. Shouldn't drop below 10 at all if you want to be safe.

That being said, those numbers are fairly typical for a stock lift pump. And suddenly dropping to 4 is also typical for the newer replacement version of the stock lift pump. What happens is, you are driving along and everything is fine, then the internal bypass that is built into the newer pumps suddenly opens and starts circulating fuel within the pump, causing the pressure drop.

The bypass was meant to open up only if the pump failed, in order to keep the truck running long enough to get it to a safe place. Unfortunately I found that after my pump got some miles on it, the bypass would sometimes start opening while the pump was running fine, and then I would have 4psi until I shut the truck off and restarted.

Ditching the stock pump for the Raptor was the single best thing I've done to my truck. It might be your time. With the Raptor you just set the built-in regulator to whatever you want, mine is set to 16 at idle and drops to 13 at wide open.
 
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i have had 4 lift pumps on my pickup and i finally broke down and baught a raptor... on for 4 days and im happy with it for now and on another note most my lift pumps only lifted 6 to 7 months if i was lucky
 

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Dont know about the condition of your VP since you're fuel pressures haven't been good but no matter, stop buying OEM lift pumps. Not only do they cost about $200 with no warranty, the Raptor will cost about $400 and has a warranty.:thumbsup:
 

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Dont know about the condition of your VP since you're fuel pressures haven't been good but no matter, stop buying OEM lift pumps. Not only do they cost about $200 with no warranty, the Raptor will cost about $400 and has a warranty.:thumbsup:
I put a 100gph raptor on my truck 2 weeks ago and all was good for about a week and now every time i shift through gears my low fuel pressure light comes on which means pressure is dropping below 5psi, im not sure if i should bump the adjustable regulator up or not seein how it was fine when i put it on the truck.
 

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I put a 100gph raptor on my truck 2 weeks ago and all was good for about a week and now every time i shift through gears my low fuel pressure light comes on which means pressure is dropping below 5psi, im not sure if i should bump the adjustable regulator up or not seein how it was fine when i put it on the truck.
Install a fuel pressure gauge.
 

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Install a fuel pressure gauge.
Everyone keeps telling me that everytime I ask and someday I will put one on it but for now I need to know if I should adjust the pressure regulator or not?
 

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Like others have said get it up around 15-18 psi. but dont over pressurize it, I've been told that can damage the vp too.
 

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Like others have said get it up around 15-18 psi. but dont over pressurize it, I've been told that can damage the vp too.
 

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Everyone keeps telling me that everytime I ask and someday I will put one on it but for now I need to know if I should adjust the pressure regulator or not?
The reason everyone keeps telling you to get a fuel pressure gauge is because a warning light can only tell you so much, and thats when pressure is TO LOW. You want to know more like whats happening at idle, cruise, WOT, etc..... You could try and simply turn up the regulator so the light goes out but then you'll have zero idea whats happening. Plus, right now you're only assuming that the warning light is even accurate. Lastly, if your fuel pressure was good but is now not then it would depend on where you're warning light is reading the fuel pressure. If its reading after the fuel filter (like it should) then your fuel filter may just need to be changed. But if your pressure is being read before the fuel filter then there's a problem with either the supply lines plugging or the fuel pump itself.:thumbsup:
 

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fuel pressure guage

Some people don't like to be told what they're not interested in hearing. I first found out about the fuel pressure issue on this forum and getting a guage was what told me my OEM and then the replacement lift pumps were no good. My light never did come on! I monitor my fpg frequently but if he wants to fly in the dark and guess at what's going on I guess that's his right.
 

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Harbor freight has that $20 test gauge kit.
Hey thats worth getting one just to keep a check on the in cab gauge accuracy. Might have to pick one up.:thumbsup:
 

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I have one of those Harbor Freight kits and it works very well although it screws onto the fuel filter test ports a little funky. Threads must be a little different, but half a turn is about all it needs to seal for a quick test.
 

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Careful using the fuel filter housing. It's made of pot medal. I cracked mine. Pipe threads are a friction seal so the further you screw it in the more the threads expand against each other. I got a used housing and a big line kit from the filter to the IP. It comes with a steel fitting that won't crack to tap for my fp gauge. Using the filter taps for a test gauge is ok just don't tighten it to much. The front tap is post filter.
 

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Rescue Tower
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Everyone keeps telling me that everytime I ask and someday I will put one on it but for now I need to know if I should adjust the pressure regulator or not?
How the heck can we tell you if we don't know the pressure it is at. If you light comes on at 5psi then that is to low.
 

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Careful using the fuel filter housing. It's made of pot medal. I cracked mine. Pipe threads are a friction seal so the further you screw it in the more the threads expand against each other. I got a used housing and a big line kit from the filter to the IP. It comes with a steel fitting that won't crack to tap for my fp gauge. Using the filter taps for a test gauge is ok just don't tighten it to much. The front tap is post filter.
I've never seen the test gauge screw on the housing itself. I've only seen them screw on the schrader valve fitting that extends off the banjo bolt head? And you're not going to crack that.:thumbsup:
 

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I've never seen the test gauge screw on the housing itself. I've only seen them screw on the schrader valve fitting that extends off the banjo bolt head? And you're not going to crack that.:thumbsup:
Didn't the filter housing change in 2000 or 01? My banjo bolts don't have the shrader valve.
 
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