New Fass and fuel pressure bouncing or surging?

[Frankstein]

Hello, I've installed a Fass titanium 150gph and now my fuel pressure bouncing  it goes from sometimes 14 to 20-24  and goes like 18-20 -21-17-15    bla bla bla ...   change rapidly .   I have an edge jwa  with that electronic sensor. I dont think its the sensor it was good.  The motor pump goes like on-off on-off   .. .   I drive the truck and I run fine even on WOT ...    I take the suction line in the stock suction tube from the tank. run the 1/2 line to my stock fuel filter canister and put a 3/8 line from the canister to the vp44 to keep my banjo bolt and the pressure sensor at the VP44 .  It's bad that fass don't give a fitting to fit a sensor with the kit!     So if anyone can help me or already had this kind of problem of fuel pressure fluctuation will be greatly appreciated  for tip and trick .       Francis

[mopartechnician]

I would start with a mechanical gauge. Just because you think the sensor is good, doesnt mean it actually is

[Frankstein]

Yes more accurate than electric.  Do you know where I can buy one not so expensive with all fitting necessary?   thanks

[joecool911]

Everyone needs a mechanical test gauge. I have a "T" schrader valve to test my fuel pressure with a test gauge.

[Ilikeoldfords]

Definitely be looking around for a mechanical gauge. Not really anywhere cheap anymore if you want a good gauge. It almost sounds like you are sucking in air somewhere. Does is start and run good?

[Frankstein]

Yes first I'll try with a mechanical gauge.  The truck start good at any time after a day or night parked or just after turning of .   when driving it seems to have no problem .  no hesitation even on WOT.  I had a little leak on one fitting at pump on line to vp44 but tightened it and now OK but same thing.  The motor sound  like bizz buzz  bizz buzz ....  like pumping pumping less. ..     I was thinking the stock suction tube or problem???     thinking of buying a tank sump but don't know if it's necessary.     

[Ilikeoldfords]

I would double check pressure with a mechanical gauge before spending much money on anything else. If you still have a problem with the mechanical gauge, I might get on the horn to Fass and see what they say.

[Frankstein]

Yeah thanks I'll try that!   

[Mopar1973Man]

Well this is kind of the reason I'm planing on doing the electric gauges and see if I can find way to resolving some of these weird issues. I'll always have my old school mechanical gauge as well but let's see what I can figure out for the electric gauge.

 

http://forum.mopar1973man.com/index.php?/topic/9042-gauge-time/