Holley FPR Issues

This is a brief video discussing how the Holley fuel pressure regulators such as those integrated into the Sniper EFI systems as well as the standalone Holley 12-875 filter/regulator can become clogged post-filters. This results in a failure to regulate and over-pressurization of the fuel system.
It is possible to clean the clogged component and the parts to rebuild the regulator are not particularly expensive.

[@cartelclassics1238]

I just went through all this with a sniper unit intermittent running issues on stalling..took apart to check the regulator put a gauge on it 75 PSI. all the powdercoating inside the regulator area was coming off. super poor design !!! spend 2 hrs with a Dremel and small pic removing every trace of powdercoat. I'd already plumbed return line otherwise I would have used a wix LS fuel filter if I'd known that's the PSI needed. I removed all the holley regulator and installed a aeromotive one w/ a guage.. so far hasn't not started yet.. Holley should honestly have to recall every sniper that's been powder-coated because it's going to be a problem for every single one eventually

[@Tartan1206]

It may be coming from powder coating breaking down within the fuel pressure regulator area

[@scottwiest3267]

Wow! I was just looking at the option of using the shorter return line option too. I will be installing my Sniper Efi setup on my 69 hopefully soon. The motor is being worked on and will be dyno'd. I plan to begin plumbing everything in the next few weeks. Great videos!!!

[@AmbiVe]

Thanks, I'm glad it could be of help!

[@abedanielspictures]

I'm glad you found the problem before me!

[@AmbiVe]

At least it's documented for others now 😉

[@anthonymetoyer8878]

So what I found out with mine was when they powder coat them it don't stick and when the gas get in the regulator housing the paint comes off. Make sure you look in there and clean all the paint from inside the regulator housing.

[@AmbiVe]

Good to know, thank you!

[@dividingbyzerofpv6748]

Just went through PSI reading a varying PSI from 75-80psi. Pulled the FPR and saw the debris. Reinstalled and still high, probably because I pushed on the center of the FPR. Pulled it back out and remassaged the cap to make sure it was not dented. Reinstalled and back to 62 PSI. Guessing debris from PTFE lines being made. Grabbing a 2nd FPR to have and try to install it while using a socket or a Brake Cleaner cap to press it into place from the edges. If that winds up being a problem still then I am yanking the FPR from the holley, putting the cap back on, and running an external Aeromotive return style FPR since my lines are already run.

[@dividingbyzerofpv6748]

Also holley suggests a 10micron fuel filter in line ahead of the sniper unit. I had a 40 micron but swapped for a 10micron after this nonsense with that FPR screen. Since the filter is under the car it still gave me around a 4 foot run of hose that may have had some debris. Question is if the FPR has that debris caught in it what do the injectors look like? With a 10 micron in line I can probably ditch the screen on the FPR as well since it so small it should just go back to the tank bypassing the FPR and not causing a failure

[@AmbiVe]

That would be my thought. I swapped to a 10 micron filter from a 40 micron at the engine before the Sniper, but who knows what made it into the Sniper, so I have been keeping an eye on it. I still don't understand why you would filter the fuel return at all. If I continue to have issues with the Holley FPR filter combo, I'm going back to a feed and return setup with an Aeromotive like my other cars for piece of mind.

[@mosesbennett8478]

So are you suggesting that we could run the fuel pressure regulator without that screen? As long as we have a fuel pressure regulator somewhere along the feed line? I hope that didn’t sound to confusing!

[@AmbiVe]

Based on what I saw taking it apart and with my fuel sock in place, I don't see why not. If you were nervous, you could just add another filter ahead of the regulator. I probably won't if I give up on the included one.

[@stingray7028]

I have the shiny sniper and my FPR was full of black substance. I have in tank pump with sock, after pump filter and a before carb filter. So where did this stuff come from ?? I believe today’s gas is breaking down the hoses inside and making the mess.. just my opinion. So I’m going to run all new steel lines and eliminate the hoses.

[@AmbiVe]

If you haven't tried it, look at the copper-nickle tubing. It bends and flares much easier.

[@matt10192004]

Installed mine this weekend. Ran good for 15 min at 60 psi. Suddenly jumped to 100 psi and then fell to 20 psi and died. Ordered a new regulator. I have a carb regulator as well that I may install and remove the Holley regulator all together. 1500 bucks for 15 min didn’t make me happy

[@AmbiVe]

I definitely think their quality control and overall design of some of their regulators are questionable. They seem to make decisions to engineer for failures that can be easily avoided.

[@matt10192004]

New regulator arrived. Removed the old. Couldn’t believe how much debris was on the regulator filter. What’s the purpose of a pre and post filter if it’s just going to clog

[@deankay4434]

Excluding the diaphragm type pump for low PSI applications, their are only 3 types. You have a roller cane pump. The metal is coming from inside the pump as say GM used this pump, but on TBI units w/13 PSI max. I have seen fuel pumps manufactured and surprisingly to me, the internal magnetic material is magnetized after assembly. Then (ACDelco) runs test fluid thru them, monitors “db noise”, pressure with correct system specs, amps, dead-heads the pump, then open flow current & volume. It takes 15 minutes per pump as they do two at time. Yours has a metal rotor with slots & round inside bores. Each are fitted with best described as brake line slices in 4mm lengths. Where I was at, they also performed tests, non-destructive and destructive testing both on alleged fail field unit returned during the warranty period. This pump design with two different parts can produce 68 PSI all day long. The problem lies with the fitment & finish of internal pumping parts as centrifugal force causes the roller to push tighter against the outer ring to produce this higher pressures. That is why they are limited to low pressure. High pressure pumps I saw are 2 stage with a balanced rotating rotor with angled vains w/80 fins within a 60mm diameter. The inlet had a CNC cut groove 2/3rds around the bottom plate that tapered off into a 2.5mm hole to vent air generated by cavitation that occurs at low pressure to high vacuum at 27” Hg to vent. Then the second rotor, smaller in dia. squeezed the fuel higher yet. This fuel is pushed up passed the armature, commutator plates, brushes and out the top past a ball bearing & viton seat and outlet. These produced 82PSI dead-headed and ran regulated at 52PSIG at 140 gallon per hour. They have a precise oraface to drop GPH and run at 7.2-7.5amps. This is in almost every GM vehicle. I am not saying your pump will fail soon or get noisy but just the least expensive design. I have work on EFI vehicles since 1976 when only 2 were made & sold. Not mechanical or CIS systems, true electric injectors with pumps. Motorcycles, every import the Air Force guys could bring home, domestic and 3 DeLoreans a guy had! No one has a filter on the return side. Been there, did that, got the tee shirt. DK. ASE Master Tech since 1978, UTI, ACDelco instructor, retired. I think this a CYA for Holley. I know enough about their system, we’ll never mind. Have a nice day!

[@scottwiest3267]

Would be possible that the new tanks need to be coated internally prior to new use? Came across a few other people mentioning the micro silver chips in their filters as well. There are internal tank sealers available on the market. Just curious.

[@AmbiVe]

Good thought. They shouldn't, but it's possible that the coating used from the factory was defective. Most aftermarket coatings will have a much shorter life than something produced at the point of manufacture against clean, prepared, metal.

[@jgvford]

about a month ago my pump started screaming on and off... the sniper ran like it was starving. Does this sound like what happens when the return screen is clogged ? my cars system is 3 years old and about 1000 miles ...do you have a video of removing the regulator filters ?

[@AmbiVe]

I didn't, but it's not too complicated. There are some examples online, but basically you just unscrew the end (hopefully without damaging the finish). I used some rags to protect it, clapped it gently in a vice, and turned the end off with a padded pair of pliers the last time. You could probably do it with a strap wrench as it isn't extremely tight. The hardest part is getting the little tiny screen out without damaging it or any of the o-rings. Before you take it apart, you might check what the fuel pressure is. If the return screen is blocked like mine, the fuel pressure should keep creeping up or have jumped well above the preset.

[@jgvford]

@@AmbiVe how do i check fuel pressure ? is it some where on the little screen ? thanks for gettin back to me .

[@AmbiVe]

You'll need a fuel pressure gauge in-line after the pump. If you don't have one, I would think about getting one at some point, but then you might as well assume the screen is clogged since it's not that hard to disassemble and clean. Just take your time and you'll be surprised how easy it is if you Google a picture of where the end unscrews from. They sell replacement parts for it on the site if you do damage the little screen, but I'm tempted to just leave mine out next time as I don't know why they are even filtering the return. Good luck and have fun with the project!

[@jgvford]

@@AmbiVe thanks.... i did order a 10 micron filter and i did order the other one today. you video helped so much ... thank you

[@jgvford]

today i put a Holley fuel pressure gauge on and the car stayed in the range of 56-60 psi... now after the car warmed up i heard a whining coming from the gas tank area .... so what now ? pull the electric fuel pump ? and how would i test it ?

[@AmbiVe]

That sounds like your regulator is working fairly well. It's possible that the pump is working hard for some reason and causing noise or it may have mechanical issues. Do you have an in-tank fuel pump or external? Do you have a screen on the pickup? Was the fuel tank clean and new? My initial guesses based on your info so far would be: 1) The pump itself is having issues. 2) There is an intermittent clogging issue. 3) Your fuel is becoming aerated due to the level, return, or pickup location. Happy hunting.

[@louiscrooker9851]

Why not run external regulator?

[@jgvford]

have an in tank pump .... not sure what company . when the screaming noise was coming from the rear of the car , the pressure was still good ... not erratic..

[@AmbiVe]

My intank setups have made noise before if vibrations from the pump are transmitted to sheet metal, if there is air being pulled into the system, or if the pickup or return are being restricted. When it's making noise, you might need to use the screw driver trick or a stethoscope to narrow down the source.

[@jgvford]

the tank was clean and new when the pump was installed.. i took most of the fuel out because i thought i might be changing the pump.

[@terryseamanster3856]

Did you consult with holley and ask how the contamination could pass through the whole system?

[@AmbiVe]

I reached out to support but did not get an answer back about it or another issue I found. Usually they are good about responding, so I took the lack of a response as an answer. Once I find out if it reoccurs with these changes, l will reach out to them again.

[@terryseamanster3856]

@@AmbiVe it must be a very fine particulates to pass through the sniper unit itself. Those orifices are tiny. Keep us posted if you hear anything from the holley empire.

[@AmbiVe]

I will. Supposedly this integrated filter is 10 micron, so it's incredibly unlikely that this would make it through a hydramat and 10 micron filter.

[@richardmarquez3394]

SAME ISSUE HERE $415 dollars and when it’s time to shine , it did not 😢