I just deleted my PPRV after chasing a fuel pressure issue (which it fixed and woke the car up) but I think my PPRV was failing not just a general restriction.

If I blow through the fuel pump side input into the PPRV air instantly starts to come out the regulator bypass outlet that goes back into the fuel tank. so I believe my fuel pump was working over time to make up for the pressure lose happening in my tank cause of my broken PPRV.. and it kinda shows that I instantly gained 3% of fuel pump duty cycle back (from 23% fpdc at idle to 19-20 fpdc).

I have however started to pop the top fuel injector orings out. Spraying fuel everywhere etc.. Ive been lucky but not driving it until I get this squared away.

I may buy a new fuel pump assembly (which includes a PPRV. I cant find the PPRV's stand alone part number) and just get the PPRV back in there but other forums and my tuner do not believe the PPRV delete is my issue .. even though ive had this thing supercharged for years, multiple engines etc.. Ive never popped a fuel injector oring until the PPRV delete.

Or Try some other fuel rails.

Everyone is suggesting my fuel rails are just not fully seated or aligned. Which I'm going to pop them off and reseat them (for a 3rd time).. I just don't know WTH.

Just curious if anyone has PPRV deleted in these cars and what experience you had. Thanks.

You mentioned your SC'ed. Whats your current fuel setup?

Heres a picture break down (everything there minus the PPRV in the picture of the fuel assembly).

https://drive.google.com/file/d/15JLeJkBtSuiIth3hWwrDMXN-HkTAEdQ7/view?usp=sharing

but upgraded wiring, upgraded fpdm, aeromotive340 or 320 ive had so many in there, upgrade alt/alt wire, ford racing #39 injectors.

I'm not a fan of deleting the PPRV however the guys that go this route normally have their tuner work the kinks out within the tune. If the fuel pressure was high enough to pop an injector o ring then pull the FRPS and smell the vacuum port, if its blown then the port will smell like gasoline. Chances are it probably blew out too.

The only thing I would do to the hat is re install the PPRV and ditch that corrugated hose for a piece of submersible fuel line.

Ive been continuing to pop the vacuum line off the FPRS and smell. Nothing yet.

I will likely get a new or barely used PPRV and get it reinstalled.

I datalogged a cold start, datalogged the test drive. the max PSI i saw was 65PSI on the start. 55PSI max during the drive.

Which everyone is saying thats not enough to push an oring out... but it is. I think the crown vic fuel rails are slightly different from the 99-04 mustangs... and possibly the injectors sit lower in the bore...

Thanks for the reply MuscleMerc! appreciate it.

Just an FYI if your getting fuel pressure from the PCM it isnt 100% correct. The only way to verify static fuel pressure is to put a gauge @ the schrader valve.

Yep I read all about the delta pressure based off vacuum FPRS. so I have an autometer gauge in the glove box... I just cant datalog it... and its hard to see when driving.

I will need a second person to watch it to see the actual pressure.


my FPDC at WOT before the PPRV delete was near 98% im just hitting 80% right now... I feel that is not all the PPRV's fault its more that it was broken/failing... so a working PPRV would likely not see that big a difference when removed.

I reset the rails/injectors yesterday. on lunch today. I will KOEO to build the pressure to 75psi (where it stays) and see if any orings pop out (I suspect they will).

Alot of people are recommending the fore innovations fuel rails.

I have a spare manifold/fuel rails/injectors on my work bench. There is just little to no play for the rails (same as in the car). I dont know how much more I can adjust or which way to adjust them. The injectors seem straight up.

Someone also pointed me to this post were they fixed similar issues with the tune, go to POST 42: https://www.modularfords.com/threads/945...hlight=fly+wire

I think I need to get a PPRV back in there once I can find one heh.

Do u wanna remove the PPRV To stop the hesitation? When you lift and the fuel pump slows down without the PPRV FUEL IS ALLOWED TO BACKFLOW THROUGH THE PUMP. This reduces line pressure and the fuel pump response isnt as dramatic so the fuel pump continues to run at a higher duty cycle instead of just basically shutting down,I deleted mine because my pump has a check valve,have u maxed your pump out?

I’m running stock rails at 460rwhp,they are doing just fine,I run a aeromotive FPR.

Hey BlackNFast, are you still returnless setup?

I removed the PPRV because it was broken/leaking on the regulator part (not the check valve per say but that was slightly leaking too). My pump also has a check valve built in but it doesnt have the regulator part built in like the PPRV did.

At high RPM/WOT the PPRV (regulator part) was just dumping fuel back into the take before any pressure was built up.

So I was near maxing out my pump/duty cycle one I removed it, my FPDC dropped dramatically, My fuel pressure at WOT was normal/expected.

From what I can read/gather the stock rails are good up to 500HP+ but what they cant handle is 60-70PSI+ fuel pressue...people start to get injector o-rings to spit out... same issue I am having.

I was looking at replacing the PPRV with a new one from a full assembly or everyone says their issue was resolved with new rails... Im looking at the MMR rail kit, with an aeromotive adpater for the stock FPRS.

Quotes from mustang users:

"I only changed them out because they didn't seal very well over 60psi of pressure. The cups the injectors sat in were getting bent out of shape and weeping fuel. Other than that they worked just fine."

"indeed. mine worked perfectly fine until i added a BAP and i guess the extra pressure did it in because it started blowing #4 o ring...changed fuel rails and it hasn't done it since."

"Thanks young gun. Same thing is happening to me now. Running a bap, modded fpdm and 320lph pump with pprv delete and my rails keep popping o rings out. I even bent both rail tabs like you guys but they still pop out'


Thanks to both BlackNSlow and MuscleMerc. Appreciate your guys replies/time.

BlackNFast I meant. I spaced cadeted and meshed two names in my head together.

Ha,no problem man..I’m sure I’m still slow too many!!
No,I’m on the stock fuel system which is “Return style”.

What PSI do you have your aeromotive regulator set at?

I will have to double check that,hang tight.

Just to update, I ended up reinstalling the PPRV. I suspect my old one was leaking the entire time, making the aeromotive pumps work harder then it needed to create the pressure needed (specially at WOT).

I ended up buying a whole new fuel pump assembly (PPRV included etc..) and bought a DeatschWerks DW400 In-Tank Fuel Pump w/ 9-1043 Install Kit For 300ZX- 9-401-1043.

I drilled the fuel hat and installed a
QFS Fuel Cell Electrical Bulkhead Fitting For 10-12Ga Fuel Pump Wires for upgraded 12 AWG wires from the DW fuel pump to the upgraded FPDM.

Everything has been running great. my FPDC has dropped from 19-21 (multiple aeromotive pumps 320/340 with my leaking/hard to blow through PPRV) at idle to 11-12 with the DW400 and the new PPRV. I believe thats from the new PPRV allowing proper flow without loss and the bigger


Picture:
https://drive.google.com/file/d/1BwbI1T-NMR2NBEoT9Q7puOR8T4PWbGBI/view?usp=sharing

That’s great man,They make great pumps and glad u got it running good.