MONTE CARLO High Fuel Pressure

[YungFlip43]

Is there anything I'm missing that can cause high fuel pressure using new Spectra fuel sender, external fuel pump, and Corvette filter/regulator? I'm pretty sure my lines are correct. 3 line sender (supply on left, vent in middle, and return on right). After some other issues an open injector was causing iDo get 58ish psi at idle, but when my tuner was tuning the car iSaw it go to 80 and 100 psi (may have been during revs iCant remember). Car was not in gear, just sitting on jack stands. iBought another regulator, but iSaw something about a restriction with the Spectra fuel sending unit? I looked around for the right diagram for the sender. What iFound had the lines wrong to me (link below) bc it showed the supply on the left (3/8), return in the middle (1/4), and vent on the right (5/16). I'm really curious about that in tank restriction comment iSaw. The person who asked never got a response and I've seen someone else bring that up before.

Here's the YouTube link iScreenshot the sender unit from:

See how the middle connection is open at the top of the tank (red), and the right connection has whatever that is attached at the top (blue).

 

[YungFlip43]

Just found another video thats basically saying the other video was right and im wrong lol. Guess that lil thing hanging is a vent itself.

 

[YungFlip43]

iDid the swap of the lines as Spectra stated and now the car wont even start lololol. Ill swap them back on Sun and see if that caused the no start or something else.

 

[Tony1968]

What pump are you using? Anything larger that 255lph is too big for the vette filter regulator.

 

[YungFlip43]

What pump are you using? Anything larger that 255lph is too big for the vette filter regulator.

Msd 2225. In the past when the tuner was tuning the vehicle the fuel pressure exceeded 80psi at times. I’m trying to figure the ins and outs of this type of system so iCan narrow down the issue.

 

[YungFlip43]

Msd 2225. In the past when the tuner was tuning the vehicle the fuel pressure exceeded 80psi at times. I’m trying to figure the ins and outs of this type of system so iCan narrow down the issue.

iThought that sporadic spike of pressure was caused by how iHad the lines ran since where iHad the return going had that valve thing on the sender.

 

[Tony1968]

Sounds like your regulator isn't sending fuel back to the tank or you have that line incorrectly installed.

 

[pontiacgp]

iThought that sporadic spike of pressure was caused by how iHad the lines ran since where iHad the return going had that valve thing on the sender.

I just had two ports on the sender I had so I used the 5/16 vapor return that has the check valve and line reducer. I didn't realised that valve was there and that caused the pressure to sit at 80 lbs. I removed the sender and cut the pipe so it was an open 5/16" port. After that the pressure was fine at 43 lbs and I can regulate it up or down from there if needed, after that I changed it to GN tank with with the in tank pump

 

[YungFlip43]

Sounds like your regulator isn't sending fuel back to the tank or you have that line incorrectly installed.

iHave another one I’m going to swap out today.

 

[YungFlip43]

I just had two ports on the sender I had so I used the 5/16 vapor return that has the check valve and line reducer. I didn't realised that valve was there and that caused the pressure to sit at 80 lbs. I removed the sender and cut the pipe so it was an open 5/16" port. After that the pressure was fine at 43 lbs and I can regulate it up or down from there if needed, after that I changed it to GN tank with with the in tank pump

was hoping you or Fleming442 chimed in. Yeah iSaw 2 people before saying they cut that off in the past. And when IHad my return going to that 5/16 the pressure would stay. Is a roll over valve the same as a checc valve? Bc that’s what Spectra called it....a ROV. Since that rep told me that was the vent line iThought that’s what it was. iAlso bought and put an external one in that line (thought that could be an issue also). But it seemed stupid for the return to be 1/4. That’s small as hell. What’s your line reducer for? You’re using 3/8 hose?