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99 Vp44 truck cranks slow and then quickly sounds like a very weak battery condition as far as the starter sound. It sounds like the starter is not giving enough power to turn over, then it barely starts. When it starts, it runs great(like usual). I even had someone else test my batteries and they are both new. I checked starter wiring, and it is all clean and tight. Any suggestions? Starter? it's about 3 years old.Thanks ahead of time,Will

So after 10 months of no CEL I got a lift pump circuit code(230). I am not using that circuit and the plug has been hanging there for a while now( 10 months). I also noticed that the grids never cycled after I started. The wts light went on for about 2 secs then shut off. The CEL turned on before I even started it, I just turned the key to the "on" position and it illuminated in about 1 second.... Any ideas.... That was the only code. I can clear it and it will come back in no more than 2 start cycles.thanks,Will

mine is the 100 gph factory position mounted raptor....they tell you to plug it right in to factory ecm power plug.......it will not prime well with the lower speed that the 8.4 volts the ecm puts out until the motor is actually running.

thank you for offering to talk to eric, but i wired a relay harness and installed it this morning. the truck works great and starts quick and smooth. will still let pureflo know that even though it is in factory engine mounted position, they need to provide the harness in order to save people from waisted timed, and maybe a burned out ecm.

i wish pureflo would change the wiring setup for the factory mount 100 gph pump....i am pretty sure its the only pump they offer that plugs into stock harness from ecm.... i will talk to jason the vp and engineer at pureflo, and see if there is anything he can do to change that setup....maybe they will save money giving out warranty pumps.

i just finished proving that both of my raptor pumps needs more than 8.4 volts to prime itself on my truck. i will not use the factory harness for powering the raptor lift pumps. i wired my harness in and ran 12 volts to it and the fuel came out like it should....it is activated through an acc circuit i am not using and powered through the positive terminal in pdc.

it plugs into the factory harness, but i can rewire it with my new relay harness. i promise it has been functioning for about 6 months..i havent had my truck for 3 weeks, and have taken the pump out and reinstalled it 4 times. give me an idea and i will try it... --- Update to the previous post... i just want to make sure i understand this correctly....this gerotor style pump needs fluid to produce vaccuum on inlet and subsequent pressure on outlet. it should not produce vaccuum wheanythingn it is not hooked up to anything.

check with barb fitting and hose on inlet going into bottle with fuel...also it i elevated the fuel level and it didn't prime .what is the correct way to check?it is the factory quick disconnect for engine mounted pump.

there is a half tank and i double checked for vaccuum on inlet with inlet line disconnected, there was no vaccuum on both pumps....i know this is ultra rare, thats why i feel like i am doing something wrong ya know.

the first pump was fine for about 7 months, then one day it stopped putting pressure out....was it an internal polarity issue?

my raptor fuel pump stopped putting pressure out about 3weeks ago. the motor runs fine but no fuel pressure is read from mechanical and electrical gauge. checked voltage and it is good at 8.5 volts without starting it. the motor turns and there is no suction on inlet. so i told airdog about it and they shipped me a new one. i just installed it, and there is no suction. it will not prime. 2 spinning pumps, so what the heck am i doing wrong?

my goal was to get 20 psi to vp input, nothing more , but in order to achieve that i would have to set my lift pump to 22 or 23 psi. going through plumbing and filter canisteris causing 2 psi drop with a new filter. i change my filter every 10k anyway. i dont believe in waiting for pressure restriction. i would rather not gamble my new vp with 25 or 30 psi, especially if it wont make a difference in reliability.

so i spoke to pureflo tech just now and before i finished my sentance he asked for my shipping address and said they would ship a viton check ball to replace the current seal which is the "bottom end" in my pics. anyone having trouble with pureflo regulators that have a sleeve style regulator, just call them and get a free viton check ball for better sealing/priming.

i installed springs and verified that it compresses smoothly in sleeve using outlet port bore.thanks so much.

that was my other thought as well...it does fit nicely. i can compress the bottom end in smoothly yet seems firm enough for proper pressure regulation from outlet port.

1-Outlet Port--------- 2- Regulator assy.---3- Regulator assyCavity---4-Bottom seat-----5- Bottom seat # 2Here are a couple pics. The exterior rim of the Bottom seat presses flat against the machined 90 degree flat. It looks like a ball seats in the bottom seat but let me know what you think.

man...i have no idea.....i will carefully poke around in the ports and see if the ball somehow got jammed in there.... but other than that.... i have no idea... i think i will check my filter canister after that....haha --- Update to the previous post... i couldn't find that ball anywhere. not sure if this is right..i reinstalled the same assembly and viewed the output line port, i pressed the plunger which is at the bottom of the reg assembly and it is pretty firm. if there is a ball there it is going to be rock solid. i would think that if there was a ball meant to seat there wouldnt there be a radius of some sort and not just a 90 degree edge. im sure a ball will seal on a sharp edge but the way the plunger perfectly sits on that edge is kinda funny...it seems like it should regulate as is, the pressure should be much less if a ball was meant to be there but it should put out at least 5 psi, right?

i have have taken pics at every stage. you guys always help me out i figure its a chance to help a raptor owner in the future. --- Update to the previous post... if i take off the backing plate to pump, should anything pop out?

i removed the dual spring regulator assembly and there is no ball in there.... i took pics but i want to find that ball first before i post them..... u guys think i should take the output fitting off and check ?

i am taking pump out in the morning to make sure the ball position when the sleeve and spring go in. i will try to take detailed pictures just incase i cant figure it out.

i changed the 15 psi spring out for the 17 psi spring and it worked great, then i went back and put the 15 psi spring back in and the regulator which is on pump snd there is no pressure but the pump does run when bumped. is there something under the ring that the spring sits on that i could have misaligned?

that is great to know, will it cause damage on any internal vp parts to run 22 psi going into vp? during the split second that the acc circuit cuts out during cranking, my relay that powers my lift pump is off, so i know the pcm sends lower voltage to pump circuit during cranking, is this potentially going to damage vp...truck starts in less than 1 second of circuit shutting off then on.

i am doing a little experiment that is a little overkill but i like to learn about first hand the relationship between pressure, flow, and cooling with my 1/2 inch hose setup. i have machined my own adapters with vp44 and filter outlet thread pitch(12mm-1.5) to a .5" hose barb out of 316l stainless steel. there is a decrease in pressure just at the vane pump caused by a relief in restriction in internal routing. so i am working on a high grade stainless steel spring alternative for my raptor (airdog 100 without builtin filter/h2o sep ). i have got 3 different ultra precision stainless springs ....so i am charting spring rate to fuel pressure for the configuration i have for my fuel system. my goal is to achieve 20 psi at vp vane pump at idle. i will be posting my report in the minimum fuel pressure post but i need to test 1 more spring rate. the variability that people see in their return line rate is from the position of the ball valve at that particular time of testing, which is almost always at idle. my opinnion is that unless you have a 150gph pump , at almost half wot, yes you have much more fuel flow going to injectors which is helpful butmaybe half or less going to return line. my goal is to have fuel and consistant flow going to return line. i believe that in conjunction with the heat alleviation in flow going into injector pump output to injectors. if pump produces twice the rpm, we have more than twice the heat energy alleviation of that additional heat energy from above idle rpms is needed imho. now i will hopefully go forward i will follow through with my thermodynamic protocol. i would appreciate any experience i can get from anyone. i wont be using anything more than 25 psi on lift pump output. i wish that the vp inlet would allow same or decent flow without engine running.

sorry accidentally posted it twice and the delete option is not there

what is the issue with setting fuel pressure to higher levels, 20 or 25 psi so under load it can flow more volume keeping pressure say around 19 psi at wot. also I'veheard that as long as it starts then it is ok....is that the limiting factor of the pressure going into vp44?