Holley sniper fuel pressure problems. May God's grace bless you in the Lord Jesus Christ.

Holley sniper fuel pressure problems Having said that if your pressure is low then it will lean out and the ECU will add fuel/pulse width until it overcomes the lean AFR reading. However, the fuel pressure is running continuously. The PO did a lot of work on the car, before I bought it, including the Sniper EFI. A basic datalog at idle will allow use to see what the Do you have low fuel pressure making your vehicle have little to no power. And I'll show you how in this video. Pressure will not return until the car cools down. I have the Sniper fuel tank with the integrated fuel pump. Been taking my 1987 Conquest to the drag strip and at the top of high gear, the car is laying over bad. Are injectors rated for this pressure or would it be better to run 43 psi of base fuel pressure and have around 57 psi at 14 psi of boost? RPM, MAP, MAT, TPS, CTS, IAC, Target AFR, AFR Left, CL Comp, Ignition Timing, Duty Cycle, Fuel Flow, Fuel Pressure & Battery. I should've suspected the filters, but was not aware of a "gooey gunk" problem in the new fuel tank installed with the Holley Sniper. I found that many people had similar issues and the pressure regulator in the Holley Sniper isn't great and can fail. A loud fuel pump is usually an indication of fuel pump cavitation or maybe a clogged filter (s). Without it, the needle jumped around like crazy. This absolutely revolutionary product allows you to simply, safely, and professional install an in-tank pump into your stock fuel tank. I'm also returnless having the Holley filter/regulator at the fuel tank, and the return line goes back to the tank at this The Holley Sniper EFI uses “Cranking Fuel” and “Afterstart Enrichment” settings to control fuel delivery during startup. - The best option might be using a quality fuel hose, which can be attached parallel to the existing steel line on the side of the frame rails. Member. It’s run fine for a couple of years . From Aeromotive: (FAQs - EFI This could be an indication of low or inconsistent fuel pressure. Further, it incorporates a 58 PSI fuel Many people warn about excess fuel aeration if the fuel returns above the surface level of the gas tank. MAP, MAT, TPS, CTS, IAC, Target AFR, AFR Left, CL Comp, Ignition Timing, Duty Cycle, Fuel Flow, Fuel Pressure Please be aware that this is a community forum. I’m running a return style system that almost perfectly mimics the factory fueling system in a stock 80. and the problem was solved. Talked to holley tech and after describing the issues along with the racket of the fuel pump they sent a new pump. Move the truck a few feet, shut off, install new fuel pressure regulator. Sometimes erratic idle when warm as well. Large negative Learn values may indicate excessive fuel pressure and the only way Jiggle the connection and it starts, still runs rough when engine is cold. It doesn't have a vacuum referenced fuel pressure regulator. Let's take a look at the items that would need to changed or can handle the higher pressure. Low fuel pressure, fuel pump weak, plugged fuel filter, empty gas tank, bad injector, etc. It will come back up when the engine is running. To troubleshoot Hello, I'm having some problems with my Holley Sniper and HyperSpark distributor. 5-60 psi (for whatever reason), you have the option to remove the FPR insert (LINK - retain o-ring), and install a remote mounted FPR . Installed a Holley in tank pump and Sniper EFI system. I want to remove the catch can, and put Figure 4 on page 5 of the instructions that Andrew posted shows how to do it. The fuel line I'm using is Earl's rubber line. I know the LSx is supposed to have 58 psi base pressure, but I have a boost referecned FPR so at 14 psi I'm seeing 72 psi of fuel pressure. Runs -My inline Earl's fuel pressure gauge reads about 64 PSI then immediately drops to 0 PSI. (Datalogs posted with truck driving and one of it idling. Holley 2300 sniper efi fuel pump problems. Going out of the sniper I have it Y’d back into a magnafuel MP-9940 “Prostar 4 EFI” regulator and a 6an PTFE line going back to the tank. These complications can lead to poor engine performance or failure to start. Connect fuel feed and return hose. From Aeromotive: (FAQs - EFI Fuel Pressure Regulators): "Be careful using a factory OEM style filter-regulator, like those used in the Corvette, if your fuel pump flows more than 250 LPH. Running the pressure was between 20 psi & 80 psi, but stayed mostly at 70 psi then dip back & forth. I’ve got a 350 SBC with a Holley Sniper system in my 80 series Land Cruiser. (Holley Sniper EFI Loose Fuel Injector Connector Fix) May God's grace bless you in the Lord Jesus Christ. Yes, the 4500 Stealth has the 3 extra input lines, so you can hook up a fuel pressure sensor and an oil pressure sensor. Customer blew it up. At this point the regulator was still in line. The Radium fuel pressure regulator is small. So when you get the pressure sorted out you'll have to clear the Learn Please be aware that this is a community forum. However, with a little time and effort, most problems can be successfully diagnosed and resolved. I pulled the return and ran it into a can and it still ran at 65 psi. Sniper Problems 08-08-2021, 11:13 AM. One of the advantages (and there aren't a lot) of a giant 1994ish P-30 Chevy Van is the engine is inside. 11-14-2021, 06:23 PM. But after running a few minutes, the pressure kept dropping. voltage, filters, pickup tube, tank venting, etc. once it's restarted it drives as should, until a few minutes later the same problem appears. Log in. A fuel pulsation damper is just a Band-Aid for the real Many Holley Sniper EFI users have had problems as their fuel pressure is too high. The result is fuel pressure near 100 PSI. Most Holley EFI systems read 100 or 101 kPa, around here. Also a electric pressure gauge to verify my pressure. My 383 stroker was running fine with my Edelbrock 1406 600 CFM carb. 623" lift/114° LSA H/R camshaft, Trick Flow Unless the in-tank fuel pump is actually a low pressure fuel pump, I'd retain it and run it solely with the Sniper EFI. 12-02-2019, 10:52 AM. The internal fuel pressure regulator in a Sniper is a crappy design. Checking fuel pressure. Since the Sniper does not measure fuel pressure, a loss in pressure could cause the engine to run lean and the Sniper would sense that and begin to add more fuel. The fuel pressure regulator has to match the fuel pump. In the Sniper 2, Holley eliminated the internal regulator and requires an external fuel pressure regulator. 4) Whether using a Dual Sync or HyperSpark distributor, you must synchronize the timing with a timing light. If that doesn’t bring it down to where it should be, I Danny Cabral: I did replace the internal regulator and am getting the same PSI. Post Cancel. ). At startup the pump runs a few seconds, the ECU fires a prime shot of fuel, and sometimes the presure drops a bit in the process. Regarding the lines I used some hard line to braided converter fittings, and converted the hard lines to -6AN. Multiple CTS sensors tried. Fuel was being delivered to the EFI but the fuel map suggested it wasn't getting enough fuel. Final Thoughts. No change in fuel pressure, always running. Thanks all. After installing fuel gauge tried again same results but I was able to see fuel pressure Find what's wrong with your EFI fuel system. Any help would be greatly appreciated. Once started it went to 60 psi. Using Sniper 2. Check and verify the fuel pressure is in the 58 to 60 psi range. I'll still install new fuel pressure regulator when they The bigger issue is that as vacuum builds the pump will produce less and less pressure. Those sensors will not show up on your handheld, but they will show up on a Digital Dash. I had the pleasure of troubleshooting a QuadraJet Sniper. Holley Sniper EFI 4150 Super Sniper 650 with HyperSpark Ignition. It's not behaving exactly like a typical surge when the AFR will vary. After proving my Holley Sniper Failure 08-10-2024, 04:11 PM. No problems with either system since. Login or Sign Up Logging in Remember me. With motor running at idle, the gauge on the input is If software corruption is suspected, resetting the system to factory defaults can clear issues, with Holley support available for persistent problems. For testing, I'd block the return port/regulator outlet on the Sniper, run your supply to the inlet of your filter, the filter regulator outlet to one of the Sniper inlets, and then connect the original return line to the return port of the filter/regulator. Although Holley employees will take part in answering questions from time to time, your questions may or may not be answered by Holley personnel. First step is to remove it and inspect it for damage or garbage (debris). Turn on the ignition and navigate to the monitor and view the pressure that is displayed. My fuel pressure is set to 90 PSI because that's what the pump is making, I checked it with a gauge. You manually input the fuel pressure in the settings and it does all fueling calculations based on that setting. I actually didn't know it's dropping while driving, as I was checking it only on fuel prime. My Holley Performance Products has written this manual for the installation of the Sniper EFI TBI fuel injection system. If you have a 1000 HP fuel pump and a cheap fuel pressure regulator, you'll have problems. I used special pliers to bead roll every fuel line joint, before clamping on the 3/8" flexible fuel line (see pics below). Thus, Holley can not guarantee an answer or timing on an answer. Do you have high fuel pressure? Causing your vehicle to run terrible? Do you have low fuel pressure making your vehicle have little to no power. You need to measure fuel pressure at the inlet to the throttle body and ensure that it's 58 to 60 psi. Holley said there is some RFI interference which I will discuss in a minute. Holley is sending me a new wideband sensor, no questions asked, and it shipped today. Perhaps the Sniper fuel pressure regulator is clogged. 6686#post96686 (Holley Sniper EFI Fuel System Plumbing - Posts #2 RPM, MAP, MAT, TPS, CTS, IAC, Target AFR, AFR Left, CL Comp, Ignition Timing, Duty Cycle, Fuel Flow, Fuel Pressure & Battery. The Sniper has four large injectors, fuel return flow can be significant at low throttle. New Sniper EFI install, having issues with AFR spikes when up to operating temperatures. Use a fuel pressure gauge: Measure the pressure at the fuel rail. I need to decide to go with either a return style fuel system (PN 19-165) which requires a new tank (costs more) or a returnless retrofit system (PN 12-300). Using the Holley Sniper EFI software I'm not sure why, but I expected more from Holley. 623" lift/114° LSA H/R camshaft, TFS R-Series FTI Hello, this is my second Sniper installation. Holley EFI actually makes excellent fuel pressure regulators. I have a 383 stroker sbc with 9. Using the Holley EFI software (LINK), look at where the live cursor moves to during this occurrence, and manually tune that area of the Base Fuel Table (enrich or lean) & Base Timing Table (optimize ignition timing). I ran the vent port to the provided valve thingy. 351C Sniper: It's about 67 PSI, closer to 65 than 70 (glycerin gauge installed just before fuel inlet). The injection system does not transfer that much heat to the gasoline via the injection rail. There's no pressure on the foam gasket. The Sniper has been on this truck for around two years and this problem has just begun. Go Causing pressure to build in the carb or throttle body. At the same time I installed new console gauges. We stopped using the internal fuel pressure regulator on most Sniper installs due to it causing problems, and I'd never use a Sniper fuel pressure regulator with a race fuel The Holley TBI fuel pressure regulator is the constant pressure type and has a 1:1 rising rate (boost referenced) fuel pressure regulator. Changed out the pre & post pump filters today, which appears to have solved my problems. It often fails and causes problems. I've noticed when I set my fuel pressure with the car off exactly at 58. As far as But the FiTech had the pressure regulator attached to the TBI unit, so my fuel pressure gauge read spot on. It's been real hot here 100°F. 2 block, Eagle forged steel crankshaft & H-beam rods, Wiseco forged pistons, Trick Flow Twisted Wedge 11R 205 CNC Comp Ported heads, 12:1 compression ratio, 232°-244° duration/. 2) Verify fuel pressure at the Sniper with a pressure gauge. EFI fuel pumps have a wide range of psi capability; you set the exact pressure you need/want. You have a problem RPM, MAP, MAT, TPS, CTS, IAC, Target AFR, AFR Left, CL Comp, Ignition Timing, Duty Cycle, Fuel Flow, Fuel Pressure & Battery. A problem has started with after around five minutes of driving. And then the Sniper would add fuel thinking the engine was running a lean condition. The BOSCH #17025 is what fits the Holley Sniper. Setup: Running a Sniper Stealth with 12-876 external regulator. MAP is reading 105 kPa, with just key on. the cause for your fuel pressure fluxuation is because the Load this into the Sniper. I ran -8an all the way from the tank fittings to the body with a RobbMC 10 micron filter in the middle and a pressure gauge close to the body. 470" forged steel crankshaft & H A datalog will just verify a problem with the fuel pressure, injector duty cycle, pulse width, etc. 15 min wait/cool down will build pressure and start and run fine. The A/F ratio starts to go past 20 and the truck lays down on itself. But when you do it this way, you have to confirm that your fuel pressure regulator can actually regulate the fuel pump. First, check the fuel pressure. It dropped psi to about 37. 623" lift/114° LSA H/R camshaft, Trick Flow R-Series FlowTech Induction Comp Ported intake, BBK 80mm throttle body, Holley Custom lines for holley sniper efi in an f hody camaro. 700R-4 ProBuilt, Moser 12-bolt with 3. With the vacuum disconnected, it has 58. After a few tries, I was able to get the car to start, but I'm also chasing down some other issues that may or may not be related. Hi all. This also pollutes the Learn Table. Correct fuel pressure is crucial for the Holley Sniper EFI. The Bosch regulator seems to have calmed the fuel system down. It assumes it's 60 and meters fuel accordingly. 790#post104790 (Holley Sniper EFI Alternator Information For EFI Applications) May God's grace bless you in the Lord Jesus Christ. Each fuel injector cover has two options for fuel feed Curious if any of you have experience not getting power from the Sniper relay to the fuel pump. '92 Other Cars - Holley Sniper and Fuel Pressure Regulator - A friend is in the process of installing a Holley Sniper system on his vehicle. What I found was plug wires routed near the rear of Sniper. The stock part is '92 Ford Mustang GT: 385"/6. Holley Sniper Kit fuel pump not enough? 03-20-2024, 05:12 PM. Your problem is fuel availability. Blew out the Sniper internal fuel pressure regulator within the first week. I'm hoping for some pointers on interpreting my datalogs. Author: A clogged regulator causes high fuel pressure. From the Holley 12-130 In-Tank Retro-Fit Fuel Pump instructions Holley Sniper EFI problems often include issues with tuning, fuel delivery, and electrical connections. He also installed a catch can. Holley EFI 12-878 Holley EFI Replacement Regulator Kit . 2 3) Some of the inconsistencies in the datalog, the Learning values, and your tuning changes tend to indicate a fuel delivery problem. The system does not compensate for high or low fuel pressure. I found an exhaust leak (at the end of the 4 in 1, just before the WBO2 sensor), but no Holley 10 micron external filter. I’ve got an in-tank pump and a return line running to the Hey cobra owners, I'm posting this here as I know you have tons of Holley Sniper experience on this forum. 470" forged steel crankshaft & H-beam rods, Wiseco 4. Put a fuel pressure gauge on it and the SOB had 12 psi of fuel Holley sends a new WBO2 sensor and I restarted the Wizard, since I didn't save a good file before it was corrupted by the bad sensor (lesson learned). I just put the fuel pressure gauge inline between the Sniper 2, and the Regulator. Let me just say that this tune attached is actually about the 9th or 10th tune that I've tried using various different scenarios to no success. I have the Super Sniper and can monitor my fuel pressure with a transducer. If the fuel pressure is a little low don't worry about that. One a sniper 2 they dont have a fuel pressure regulator in the throttle body and you have to run an external regulator. Talked with Holley tech and the decision was made to send it in as he thought maybe a bad injector driver. Says it's running lean, but spark plugs look like it's running rich, spark plugs were just replaced. I haven't had this problem since install, it's something that has come on in the last several months. Of note, yes, I have RPM on 3. - Fuel pressure has been verified at the Sniper EFI throttle body and is between 55 & 65 psi - All wiring has been tied away from potential hazards such as the exhaust, fans, pulleys, spark plug Holley Dual Sync Distributor Timing Control 199R11369 Date: 7-28-17 . Many Snipers seem to get a clogged or defective regulator. Check the fuel filter: Make sure it’s not clogged. After shut down it may not restart due to no fuel pressure. I figured a new one would at least temporarily improve the situation. Install was straightforward without any problems, except it was shipped without two vacuum nipples installed on the rear of the throttle body. -The engine starts and runs fine and the fuel pressure gauge reads 64 PSI. It has Edelbrock heads, Edelbrock intake, a small cam, long tube headers, Magnaflow mufflers, etc. Engine runs again like a scalded ape! Sheez. If you have to wait a few minutes, it sounds like it could be a fuel pressure problem. I'm planning a Sniper EFI install for my '69 Nova. If internal pressure is low, the opposite is true, we would expect to see high Closed Loop values and high injector flow commands. Start a list. On my friend's '66 Charger, we used a HyperFuel 40004-9 (Fuel Tank Return Line Bung). installed it much quiteer but almost I've installed a Sniper EFI with the Holley Dual Sync Distributor and an MSD 6EFI Ignition. I did a bunch of research on the Holley forums. I haven't had any major issues with the system until recently. First sensor I ordered myself, was wrongBosch 17014 does fit the Fitech harness, but does NOT fit the Holley Sniper. The fuel flow in the log is the commanded fuel flow from the Sniper. The psi ratings are for performance (volume) information only; they're not a pressure setting. An EFI fuel system needs two filters: I wouldn't use a big 340 or larger LPH fuel pump with the little Sniper fuel pressure regulator. If the CTS reads 10° or more higher than the MAT, the CTS is a faulty Holley supplied unit and it must be replaced. If you don't have one, install a pressure gauge at the inlet to the Sniper to confirm pressure. When the fuel pressure is too high, from a clogged regulator for example, the system compensates by trying to remove fuel. It's wired as shown in the attached diagram (checked about ten times with multiple people checking it). When the car is sitting still there is no fuel splashing the gasket. Holley told me I do not need a pressure regulator beyond what is built in to the sniper. Holley Performance Products has written this manual for the installation of the Sniper EFI TBI fuel injection system. You can also add the Holley EFI analog gauges, but that still doesn't solve your problem since the Sniper doesn't RPM, MAP, MAT, TPS, CTS, IAC, Target AFR, AFR Left, CL Comp, Ignition Timing, Duty Cycle, Fuel Flow, Fuel Pressure & Battery. Replaced 2 O2 sensors 2 separate installs. I did add the Radium in-line fuel damper and it made a big difference on my fuel pressure gauge. I confirmed that the fuel gauge is working properly by conducting some bench testing. 91 gears and a I suspect that you may have a fuel pressure problem. The fuel filter should also be changed if there is I'm at a bit of a loss. It becomes a Holley EFI actually makes excellent fuel pressure regulators. After double checking all connections and checking for current, everything is as it should be. The system will not build pressure properly when there are two fuel pressure regulators in-line. Misfires cause a false My friend had a Sniper 1 and had nothing but problems with it. Sniper 2300 V8 2 Barrel Fuel Injection Master Kit installed on an AMC 304, with ~3,500 miles since initial installation. 3L SBF, Dart SHP 8. I have an older Sniper on my '65 Dodge pickup with 440. Common causes include clogged fuel filters, a failing fuel pump Sniper 2300 low fuel pressure, no start. It becomes a (bypass/return style) better. My car is the '33 hotrod with a brand new BPE 347 motor. I suspect a pump or fuel pressure regulator problem. If you're using the internal fuel pressure regulator and you see 80 psi, then you have an issue with the internal fuel pressure regulator. I used the same as you. Also the connector for the CAN Bus cable was bound near plug wires. Double check your connections and system that produces the RPM signal for the Sniper and you'll most likely find your solution for the no run problem. I replaced the fuel pump with a Walbro 255 LPH, and ditched his regulator, and hooked the feed & return back to the factory Sniper regulator. The problem is heat soak of the fuel lines. Cool, the parts that were missing made it an easy choice to use a return style pump from Carter for a 70-73 454 car given the carb/intake manifold situation. It flatlines at about 29:1 in a cyclical pattern. JoshT. Don't confuse psi ratings with what the pump is actually capable of. No, fuel psi at 52 will not keep the Sniper from working. Just wondering if this was normal or if I'm potentially having a fuel pump problem. Junior Member (Holley Sniper EFI Fuel System Plumbing - Posts #2, #6, #14) May God's grace bless you in the Lord Jesus Christ. 3L I think I washed out a cylinder or multiple after my Sniper EFI install. He discovered that this Holley Sniper (and perhaps all of them) does not have a fuel pressure regulator with it. With the vacuum reference hose on the fuel pressure regulator connected, the fuel pressure at idle is 51 PSI. If you have fuel pressure then you've got to dig deeper. Sometimes dies or stalls and catches itself. Low pressure can lead to poor engine performance. Holley has solved this problem for you. It is not a measure of the fuel flow and/or pressure from the pump. Your datalog does not have an RPM signal. I’ve got a 3/8” feed and 5/16” hard line return. Holley offers a variety of fuel pumps, hoses and accessories to complete your installation. Fuel Pump: On average, your block mounted mechanical pump will produce up to 10 psi of pressure. Sniper Problems 08-25-2017, 01:35 AM. In the Sniper EFI software (Sensors ICF - Custom #1 drop down menu), the "Holley 100psig SS" sensor is Holley's 554-102 100 psi stainless steel pressure sensor. The Holley engineers didn't provide an oil pressure (or fuel pressure) channel in the Sniper, so there's no way for the Sniper to communicate with a CAN Bus gauge. You only have a foot or two of hose and the Sniper between your gauge at the inlet and the gauge on the fuel pressure regulator. which could cause drivability problems and severe engine damage Hi. 5" TSLCD while cranking, and for more data my equipment is a Sniper with Holley Dual Sync distributor and Holley coil (purchased kit all at same time so "stuff" matched up). Hey folks, new to the forum and the Holley Sniper. Would be interested in seeing what your config file looks like, and what AFR and timing I like the adjustable fuel pressure regulators (bypass/return style) better. Also, any EFI fuel pump will decrease volume output (GPH Hi everyone! I have a '70 Dodge Challenger with a 440, Sniper 1, MSD 6AL, Torker II intake (single-plane), HyperSpark distributor, street/strip cam. Holley Sniper 2 claims to have rectified the problems with the first generation. Walbro 255 pump. Don't know if truck ever backfired. We replaced the frame mounted fuel pump with a Walbro and replaced the pressure regulator with a new one . Using the Holley EFI software (LINK), The problem with that is the Sniper is dumping a ton of fuel into the engine since it thinks it's lean. Checked fuel pressure regulator pressure, and raised it from 55 to 60. The Target Air/Fuel Ratio Table & Base Fuel/Timing Table (and MAP kPa & RPM axes/scales) should be configured using the Sniper EFI software: In the Sniper EFI software , Target Air/Fuel Ratio Table (Fuel ICF) & Base Timing Table Thanks, I'll definitely try to fix fuel pressure problem first. Second, make sure the fuel lines are unobstructed Fuel pressure should be 60 psi. Assume vapor in supply and return lines. With a return style system, fuel pressure will always be regulated to a consistent pressure at the fuel rail. If it I have a 550-516 Sniper, just the base unit with the fuel pressure regulator built-in. Fuel Pressure Problems Impacting Startup. Now running near 60 psi fuel pressure at the injector body. The Sniper EFI fuel pressure should be 58-60 psi at all times. It could be so high the injectors don't fire. I'm suspecting an ignition issue now. This must be accomplished with an EFI fuel pump and bypass fuel pressure regulator. Inspect/troubleshoot/service the If unsure, consult the Holley Sniper EFI manual or contact Holley’s support team. fuel pressure would drop to 20-30 psi and even dip at idle. I have a rebuild kit for the Sniper fuel pressure regulator. When fuel pressure is high, the Sniper will restrict injector flow to try to lean the system. Some Snipers were shipped with defective regulators and problems are common despite careful installation. It does have dual fuel tanks, and the fuel hoses are routed per the instructions to the selector valve. I installed the Sniper universal tank with internal 255 LPH pump. IF the Sniper's fuel pressure regulator won't regulate to the proper 58. I’ve seen quite a few threads for high pressure that usually seems to relate to the fuel pressure regulator. I'm wondering what fuel pressure I should run on my Boosted LS. I checked fuel pressure at idle, 60 psi. Holley EFI actually makes excellent fuel pressure regulators Danny Cabral: Yes, the Holley EFI 12-875/12-876 Filter/Regulator's fuel pressure regulator is the same type of OEM fuel pressure regulator. Turning off the engine and fuel pump for a few minutes to remove a connector may have been enough to let the pump cool a little or for the tank to vent. I capped the return and pressure pegs out when pump At this point we had narrowed down the issue to the EFI system itself. I've replaced both pre & post The Holley EFI 12-875/876 Filter/Regulator has the same small fuel pressure regulator as the Sniper throttle body. (Holley Sniper EFI Replacement CTS) May God's grace bless you in the Lord Jesus Christ. An engine that won’t start or stalls immediately may be suffering from low or fluctuating fuel pressure. I believe it was severely overheated, and this was the result. No RFI. May God's grace bless you in the Lord Jesus Christ. Would there be any problem using this line as the pressure feed line for the EFI? Yes, a 3/8" steel line is good for pressure feed. My idle fuel flow is between 10-14, smells too much fuel, spark plugs are black & wet. If it's internally regulated and setup as returnless, you shouldn't run the return through the Sniper fuel pressure regulator. Jump to Latest After installing fuel gauge tried again same results but I was able to see fuel pressure issues with engine stumbles and quitting. Going out of that it splits to another 8an to 6an Y block which feeds both “rails” of the holley super sniper (stock fuel reg inside sniper has been removed). 200" forged pistons, Trick Flow Twisted Wedge 11R 205 CNC Comp Ported heads, 12:1 compression ratio, 232°-244° duration . I'll try to run it with the alternator disconnected Andrew get a datalog. I've run through the setup Wizard multiple times to ensure that I've set things up properly (again checked by multiple people). An EFI fuel system needs Sniper EFI Tuning & Tech. There is a hack that allows you to see the oil pressure and fuel pressure on your handheld, but I don't think you can name the channels. Sniper EFI throttle bodies require 58-60 psi of fuel pressure and a 10 micron filter. Replaced one with a Holley OEM 02 and the second was with a bosch equivalent. A fuel pressure of around 58 PSI is With no changes to my Sniper setup, and no prior history of fuel pressure issues, I'm no longer getting a steady fuel-prime pressure of 58-60 PSI. Thanks. I've certainly heard that the internal fuel pressure regulators are bad, I just figured a new one would make some change to Many Holley Sniper EFI users have had problems as their fuel pressure is too high. ) No, nothing was touched and all connections are tight, cranking like a champ with good fuel pressure. If you're going to run with open exhaust, then you need to turn Closed . Electric fuel pumps only produce volume, the fuel pressure regulator creates the desired pressure. Installed the new pump and started the car and it started puking fuel through the vents on the float bowl (Holley 4150). Comment. At zero PSI show that the Sniper reads -4 (just an example). When starting out from a stop it stumbles RPM signal issues, exhaust leaks upstream of the WBO2 sensor, defective WBO2 sensor, fuel pressure, corrupted Learn Table, timing synchronization, idle IAC Position, etc. Installation was fine and engine started up. I bought a Blueprint Ford 302-370 HP engine with a Sniper already installed. The truck shudders and skips when under a load, most It was a constant 60 psi, but I didn't have backfiring then, so I'll recheck pressure. I've been running an Aeromotive 13301 external fuel pressure regulator on my mildly blown 385 SBC for some years now. I made that mistake on a race engine once. And replaced the filter Recently I installed the Holley 12-300 in-tank fuel pump/sender with integrated return line. The car starts fine and will operate just great, until it gets hot then the fuel pressure suddenly drops from 58 psi to zero and the car dies. Dart SHP block, Dart Pro1 heads, Holley Sniper EFI with HyperSpark, Comp Cams, NOS Cheater plate with Powershot solenoids. The Sniper ultimately appears to be chasing a bad Holley Sniper Air Fuel Ratio Issues & Start Up Issues Symptoms & FixCR Nuts Episode #16 Three start up issues that we encountered and fixed- Low Fuel Pressur With 90 psi, you may have a defective fuel pressure regulator, or a restrictive fuel return line. I've ordered an inline check valve. It's 1978 When I went to crank, the pressure showed 43 psi, but the car was hard to start. so the fuel sender outlet is a 3/8" to a -6AN braided hose, to a fuel filter capable of filtering 100 mocrons and flowing 100gph, to a Holley Blue fuel pump that has a maximum pressure of 14PSI. The Sniper EFI needs to be fed with 58 PSI of fuel pressure. The Holley Sniper EFI system brings modern fuel injection advantages to classic cars, but users should be prepared for So my fuel pressure has been about 72 psi since I installed the system. The truck runs better now, but cuts & pops on hard acceleration. On a recent trip it started losing fuel pressure And was barely able to move . 623" lift/114° LSA H/R camshaft, Trick Flow A high flow fuel pump will blow the fuel pressure regulator open on a Sniper and you'll end up with weird fuel pressure problems. Holley said it What I have: 454 Chevy Square Body. My pump is a wahlbro 225 unit in the tank rated up to 100psi. The Target Air/Fuel Ratio Table & I also switched from a returnless FiTech system to a Sniper Stealth. The fuel flow is ~ 3x at 2) Check your fuel pressure. Although there could be a number of issues causing this, one of the main p 6) Relating back to 1. The fuel pressure not running was 90 psi and 70 psi back & forth till it clicked off. RPM, MAP, MAT, TPS, CTS, IAC, Target AFR, AFR Left, CL Comp, Ignition Timing, Duty Cycle, Fuel Flow, Fuel Pressure & Battery. I installed a new Sniper EFI unit in my 1990 Grand Wagoneer last weekend, and when we turn the key to prime the unit, the fuel pump doesn't engage. I bought a '79 Corvette, with the OE L82, 350 engine, about 8 months ago. Here are some steps to ensure proper fuel pressure: Had this problem since out of the box new. Direct plug in and even has a longer harness. Have you checked the fuel pressure with a gauge? Last edited by 351C Sniper; 08-10-2024, 05:12 PM If you don't show any fuel pressure then fix that. A lack of RPM signal will keep the Sniper from working. Limped back to the dock and checked everything over, no stuck injectors, all grounds are good, new WBO2 sensor, fuel pressure 58 psi. She was running great and then I went to pickup my daughter from the sitter last week and after turning the truck off, she wouldn't start again, no fuel pressure at all. check fuel pressure. Keeping track of the system’s performance through regular testing will help you identify any issues before they become more severe. When the pressure is 85 psi it's going to dump fuel. The problem that I'm having is that the fuel tank, after running for five minutes, will start spitting gas out of the vent hose. Fuel pressure is good, no exhaust leaks. 1/2" hard line to front with -8 from the pump and -8 return. It has been a painful experience with the fuel pressure regulator problems, ECU problems, and it still stalls on deceleration when the clutch is pushed in at a stop. I got the regulator, but no screen in and tried that. After cleaning & reinstalling, fuel pressure is now sitting a hair over 60 PSI, much better than the 80 or so that I was getting. While it may still run, the learn table can quickly become corrupted. Does the Sniper 2 fix any of the weird problems of the Sniper 1? Does Holley provide credit to turn in a Sniper 1 AN6 to Holley sniper EFI, 60 psi. It is boost referenced to the top hat. It's pretty well documented that they have had manufacturing problems with the Sniper units, so how they get off charging $200 '92 Ford Mustang GT: 385"/6. Routinely clean and maintain the system to prevent any major problems. Pressure rock steady at 60 psi, but drops when RPM is increased. The air passage (under boost) is a small hole, located in the driver's side rear throttle bore (above the throttle blade), leading to an o-ring seal on the regulator housing; its purpose is for blow-through forced induction applications only. We can fix this. The Sniper would then dump fuel to combat the lean condition. Return-style fuel system, 3/8” line in & out, 100 micron pre filter and 10 micron post filter. Got a holly sniper on a 302 ford , in a falcon . 5 psi, when the car is I am running an Aeromotive Stealth 340 (340 LPH, 90 GPH) fuel pump with Aeromotive PWM & external Aeromotive fuel pressure regulator, -6AN braided supply all the way to the tank, and -6AN return lines plumbed to the stock 3/8" stainless steel supply line. Using the Holley Sniper EFI Originally Posted by Danny Cabral The Target Air/Fuel Ratio Table & Base Fuel/Timing Table (and MAP kPa & RPM axes/scales) should be configured using the Sniper EFI software: In the Sniper EFI software (), Target Air/Fuel Ratio Table (Fuel ICF) & Base Timing Table (Spark ICF), select "2D Table" Type (not "Simple"). The pressure started dropping and got down to around 15 psi and the engine died. 5 C/R that keeps backfiring through the exhaust. Cylinder cracked, piston destroyed, and rod bent. If you have 40psi liquid pressure at the pump but the pressure of the fuel boiling is 20psi of fuel vapors then when the injector opens the vapors vent out fast and your left with momentary drop of 20psi which can stall the engine and make restarts hard. This Holley sniper is brand new, including new tank/lines/ in tank pump ect. We recommend placing the fuel pressure regulator after the Sniper EFI throttle body like shown in Figure 4. Bad O2 sensor, the WBO2 sensor is suspect. It is the fuel pressure the system expects. Using the Holley Sniper EFI software (LINK), look at where the live cursor moves to during this occurrence, and manually tune that area of the Base Fuel Table (enrich or lean) & Base Timing Table (optimize ignition timing). The handheld only shows what fuel pressure is programmed. 10. My Holley Sniper Stealth did not come with a pressure regulator. How to Fix High fuel pressure with your Holley SniperAre you getting 70, 80 or 90+ PSI fuel pressure?This video shows the most common reason to have high fue The Radium regulator has calmed the ticking down. which could cause drivability problems and severe engine damage 6. If it's too low, adjust the regulator to increase the pressure. It doesn't seem like it should come back from Holley service that way. Idled very rich, no Learning ever even after temp, temp sensor issues, etc. Inspect the fuel pump: Ensure it’s providing adequate pressure and flow. Previous 1 2 template Next. The problem is that he only has 20 lbs of fuel pressure, according to the 0 to 100 psi When the Sniper 2 EFI system broke cover last summer, it was an evolution of Holley’s popular throttle body electronic fuel injection conversion kits—offering plenty of refinement and enhancements over the previous Installed Holley Sniper 550-511 I have sent these to Holley tech but the problem is the entire system is losing power so the log stops when it hiccups. I soon discovered my fuel gauge showed empty no matter how much fuel was in the tank. Starts up. The Sniper ECU does not make any adjustments based on measured fuel pressure. I removed to install the Sniper EFI. If you haven't yet, install a fuel pressure gauge at the inlet to the Sniper and confirm that you have 58 to 60 psi while running. holley blue fuelpump pressure erratic if you run a holley blue pump it is set at 14psi from the factory and you must run the regulator that came with the pump . rkr. I realize this shouldn't be necessary, but I'm mentioning it only because consistent fuel pressure is paramount to proper EFI operation. I have a new Holley gas tank with an in-tank pump. Join Date: Jun 2018; Posts: 36; Share Tweet #23. It's too small to support the high flow volume of a high output/racing fuel pump. The Closed Loop function in the Sniper will try to pull fuel out, but it can only do so much. 175 GPH is the flow size of the fuel filter, and it's Holley's 2nd largest fuel filter. Thanks for the questions and quick replies. I set those parameters in the Sniper for actual fuel pressure, and it works great. The fuel pump is VR2-12-3000, and the regulator I have a Sniper 1 on my Ford 302 powered Jeep. 623" lift 114° LSA H/R camshaft, Trick Flow R-Series FlowTech Induction Comp Ported intake, BBK 80mm throttle Recently replaced the engine, in a customer's truck. Corvette filter/regulator, my fuel line is almost all 3/8" hardline; and the 255 LPH Walbro pump. No bouncing and pressure was constant at 58 psi. I'm using a Holley in-tank fuel pump that they recommend and sent to me. I've had the Sniper on my SBC build for about a year and the past few months I've struggled with keeping it running right. Intermittent issues until two days ago when I fix the wire issue with new leads. We installed a bigger fuel tank vent on the fuel tank, and still after 7-8 minutes it will start coming out. That's most likely a fuel delivery problem. As you'll see in the attached datalog, after a few minutes of driving without issue, there's a few things going on. I've been having issues with the fuel flow through the Holley Sniper EFI, so I decided to replace the internal fuel pressure regulator with an inline adjusta Ultimately, troubleshooting a Holley Sniper EFI problem requires patience and attention to detail. I’ve done a bit of searching, but can’t seem to find much information on my condition which is low fuel pressure. After replacing two internal fuel pressure regulators for incorrect fuel pressure (72 & 82 psi, respectively), I installed an external fuel pressure regulator. 5 PSI and the injectors are louder. I installed an external Holley regulator. 3) Remove the air cleaner and have someone turn on the ignition and confirm that all four injectors are providing a prime shot. Once the car was running the pressure read as normal. When you see fuel flow drop it is an indication that the Sniper thinks it has to reduce fuel flow in order to lean the system out based on your WBO2 reading. 200" forged pistons, Trick Flow Twisted Wedge 11R 205 CNC Comp Ported heads, 12:1 compression ratio, 232°-244° duration/. aussie408. '92 Ford Mustang GT: 385"/6. I managed to screw up and with a lot of other stuff (both hardware and software) before I discovered that was the issue. The Sniper EFI software asked for actual fuel pressure. Although there could be a number of issues causing this, one of the main problems have to do It drops from 58psi base pressure to well under 40psi as you go up in the rpm band. I’ll try that first. Hello. Start then engine and through the warmup create a table of measured psi with your gauge versus the Sniper. Distributor is timed correctly, and runs from 20°- 26° advanced RPM, MAP, MAT, TPS, CTS, IAC, Target AFR, AFR Left, CL Comp, Ignition Timing, Duty Cycle, Fuel Flow, Fuel Pressure & Battery. Decided to upgrade firmware after reading another How solve fuel pressure problem on the Holley Sniper System. If you were able to hook up a return line then the pump is intended to be The Sniper does not measure fuel pressure. A datalog will just verify a problem with the fuel pressure, injector duty cycle, pulse width, etc. While it can move the required volume of fuel, it cannot maintain a Holley Sniper 4150 on a ‘69 Buick 350 engine in a ‘69 Jeep Commando. On a returnless system you cannot run another fuel pressure regulator in-line. Some have swapped to an internally regulated pump and still used the Sniper fuel pressure regulator and return. When the CTS reads high, the coolant temperature enrichment will be off and this can result in a stall. Sniper EFI Tuning & Tech. Every other time It would start & run beautifully. I’m logging fuel pressure with the Holley super sniper (supports 1250hp) and also am Somehow my return line got mostly blocked and my fuel pressure more than doubled. Purchased a glowshift electronic fuel gauge and necessary fitting to tie into fuel system. I had to replace a lifter in my SBC, and after getting it back together, the fuel pressure only went to about 40 psi at the initial turn on until the EFI turned the pump off (not sure if this is normal or not). 2 block, Eagle 3. Truck runs good at idle, and low speeds. be sure each component is designed to perform at high pressure. At high altitude especially I’m constantly losing fuel pressure. sidmai flppqm nldw vaacr jzyyl snkteacm drhaf ljpnz xmjn ahxgj