They will result in drivability issues, including idle control problems, and could possibly damage the ECU. You're not running your EFI system without a gauge are you? Many of these are completely normal with EFI. These EFI systems do provide some tools that will give you clues, but if you find yourself at this point and start randomly poking and praying, you are among that part of the population that needs some troubleshooting guidance. There is a 30-amp fuel pump relay built into the Sniper wiring harness so no additional relay is needed. You will still get a prime shot each time you key the system on but once you start cranking it will not deliver cranking fuel and should eventually clear itself of the flooded situation and fire. Thanks. I have it disconnected to flush any debris out.Thank you. You mentioned its use in # 9 of the top 10 Sniper EFI installation tips. Copyright 2017 Cyberspace Automotive Performance, Inc. All Rights Reserved. Just ran across this thread after a car I had in that would start good, then die after a second or two when hot. Also check your cranking voltage if it starts hard. Is this normal? 2. I call this the Happy Dance moment. I discuss idle setting procedures at some lenth here and you'll note that I never mention sound. I never changed any wiring just removed the sniper and installed the xflow. Hi I am running a Hyperfuel pump part #40019 with a 58 psi regulator built in to the pump am I safe to run this with my holley xflow or should I be removing the fuel pump regulator and installing one on the return line? EFI Systems based on Holley's world-class Dominator and HP ECU's. (Plus, it's easy to do---see this article.) 2-Barrel Sniper EFI 2300 Sniper EFI C10. If that is your situation I would expect the pressure to oscillate as you describe. Gary. Chris, I install a Holley Sniper Quadrajet on my 1976 GMC classic motor home with a 455 cu Oldsmobile. Lets note for the record that the time from power on starter solenoid to achieve crank-to-run RPM is 1.13 seconds. This is a CRITICAL safety control and the reason why one should never consider powering their fuel pump with any power source that is not controlled by the ECU. Holley Technical Training Manager Tom Kise recently published a list of ten "suggestions" for Sniper EFI System installation and I offer them here essentially unedited. Pinched or Burnt O2 sensor Wiring: Keep it high, tight, and safe. Direct to the battery means to the battery. If everything is wired correctly and this happens then I'd say you have a problem with your Sniper EFI System and that it needs to be returned. THAT'S A PROBLEM!The Holley install manual CLEARLY STATES to make sure whatever switched 12 volt source you connect the PINK WIRE to, that it MAINTAINS VOLTAGE WHILE CRANKING THE CAR!! Im not looking for timing control just upgrade to EFI. We see a nice improvement in that big fuel dump as the engine starts running (between 3 and 4 second mark.) If not, then the orientation of your O2 sensor is not your problem. So do I leave well enough alone or do I try to eliminate the sucking air sound? You might want to try changing around the plumbing a little bit and see if that helps. But as you go farther back, it only gets better. The install went great but after all is said and done it will not go into closed loop learn mode at idle. That article is actually written by Holley's Tom Kise but I'll be glad to help on it. Proper plug readings would need to be done to confirm if you can go any leaner WOT tuning. You see that the AFR trace is ar below the target AFR (pink trace.) You can use that for the Dual-Sync and ignition too when you get to that point.Running the O2 sensor on a single side of the dual exhaust works fine. It turns out that in EFI , as in life, there are no shortcuts to excellence. There must be an option that has been found to work. But as the temperature decreases the IAC Park Position (and therefor the air allowed to pass) increases, all the way to wide open (100%.). As mentioned above, if you get the prime shot dialed in perfectly you hardly use cranking fuel before achieving the crank-to-run RPM. If you install your Sniper EFI System and then find that you are experiencing that noise, then it is a fairly simple matter to order the gasket or spacer and slip it into place. Love the example at the end. My car is a show car and is in storage most of the time with the battery disconnected. Holley Sniper EFI Check Latest Price. Price Point: $$, EFI Systems based on Holley's world-class Dominator and HP ECU's. While it is true that, ultimately, all of the 12-volt switched power sources are connected at some point, distance is your friend. Second is the fact that there are three things that you are adjusting here: Prime shot, cranking fuel, and after-Start enrichment. Can I get clarity please? I know it's only 2 feet but ever inch counts. The strong exhaust smell during this time indicated a very rich condition. Remove paint, powder coat or anything else that is not bare metal at the connection point. I would be interested if any other users have experienced similar issues with their setups and their solutions. Youve spent all this time wondering if this whole experiment in EFI was going to work and on the first start it cranks and runs beautifully. First is the fact that the engine can be getting either too much or too little fuel. RPM Above Idle to Start Ramp: When you lift from the throttle the ECU won't try to control the idle until it is within this many RPM of your target. Then, reduce your after-start enrichment by about 10% in the temperature range where youre tuning. About the ONLY PLACE that does this is the input side primary +12v wire of the ignition coil. Or do as I do? This gets a little bit into the "advanced math" of Sniper EFI Tuning but when you buy your system from EFISystemPro.Com you can give me a call and I'll gladly walk you through this. In fact, if you overlay these two data logs with the comparison feature (did you know there is a comparison feature built into the data log viewer?) Pressure holds steady at approximately 50 psig when engine is off. Runs good, but dies while I drive down the road. This happens with some carburetors on dual planes as well. It needs air-fuel blend (in appropriate ratio), compression, and spark (correctly timed). I have the 12-1800 dual holley pump also. This is extremely unreliable afrer warm. It needs the tip pointed down at least 10 degrees from horizontal and at least 15 degrees from vertical I prefer about a 45 degree angle from horizontal. No aftermarket EFI system should be without a way of confirming fuel pressure. The engine starts and idles great. Hard to answer. Do you see an issue with this? But you can extend the leads using wires of an equal or heavier gauge. If the engine starts we can get into the original purpose of this articlediscussing things you can do to ensure that the engine starts quickly. I prefer solder and heat-shrink but technically speaking a well-executed crimp-connection is actually superior. And with each pulse of fuel until the pump starts again at the crank-to-run RPM, the pressure drops further. A throttle linkage extender and a progressive linkage kit. This page was generated at 05:08 PM. In fact, MOST of the points on the fuse block don't do that! Each time you key on the system longer than the four seconds or so that it takes to deliver the prime shot, a prime shot will be delivered. Featured Products Sniper EFI $7.07 - $2,457.95 471 Products View Parts author Staff Writer 1711 Posts An Article About Video tech Sniper EFI Videos Sniper EFI Tech Sniper EFI sniper Installation Start the motor with the air cleaner off and the chock butterfly held open if it stays running its the chock. Bill Tichenor. O2 Sensor Mounting: The O2 needs to be mounted 6-8 after the merge in the header collector.Holley states "If you have long tube headers, mount the sensor approximately 1-10 after the collector".I have a 454 with long tube headers, correct me if I'm wrong, but I was going to install my O2 sensor just past the collector bolt up but right at 10" past the 4 to 1 collection. Runs, then dies. To be 100% honest I was having an issue prior and flooded it. Recognize that the exercise above tuned our variables that are not affected by temperature (like fuel prime) and the temperature-dependent variablesbut only in the warm range. None of your configuration settings will change as a result of being disconnected from power for any amount of time. Pin 30: To Battery 4.) Good luck! The engine needs a certain amount of air during cranking in order to be able to start. Stay after it--you'll make it happen! From what I read it should not be installed vertically? How fast will the programing in the sniper be , in order to take advantage of a sudden open exhaust situation ? Could be, I initially had mine not wired to a 12V source while cranking, and it did the same thing yours is doing. That means at or above 55 PSI it is capable of flowing ZERO fuel. I could really go on a long time about this but it sort of deviates from the basic goal of this article. Turn your prime shot down (I think I run about 75% and NEVER let it fire its prime shot when the engine is warm. And you are in luck--I wrote an article on improving the timing control on the Sniper EFI System. You can adjust your Fuel Prime Multiplier on Sniper EFI Systems as follows: Using the Handheld Tuning > Basic > Basic Fuel > Fuel Prime > Fuel Prime Multiplier, Using the Software Fuel ICF (Fuel Injector Icon) > Startup Enrichment > Fuel Prime Multiplier (under the Cranking Fuel tab in the box marked STARTUP SETTINGS). I strongly recommend EFI System Pro. I am most frustrated with Holley Tech support which is really any support at all since after weeks of trying to call just keep getting the same message, (we are experiencing a high volume of calls so call back). Your assistance would be greatly appreciated. My situation, although related to start up, is somewhat different. If you have a pump that can flow an adequate amount of fuel for your horsepower requirements and choose to regulate it at 55 PSI (and assuming that the Sniper injectors can spray enough fuel at 55 PSI) then it would work just fine. And it may have improvedor it may have gotten worse. At the bottom you'll see AE vs TPS RoC Blanking. :-D. Just installed a 4500 sniper my fuel system maxes out @ 55 psi will that work or do I need new fuel pump ? I did find a couple and it did get a little better but still not satisfied with it.What is the ISC hold position for and why is it set @ 30? Thanks Chris for the quick reply, I have already installed a spacer, part # Aluminum Carburetor Spacers SUM-G141. Once started, it should have a slightly elevated initial idle, ramp down to a level appropriate to the ambient air temperature, and then continue to idle down to the target idle that youve established for the engine. Will the height of the return line be an issue? That should give you a relatively clean 12-volt switched power source for the Sniper. If not then stop and buy one now. Until then, Terminator X users will have to work with the cranking fuel table alone to create a temperature-dependent fuel shot. Hey Chris, I installed a Holley sniper on a small block 400, first start was great! Get this high enough that it is not limiting the ability of the engine to start, tune the other factors that enhance the engines ability to fire quickly, and then come back and trim this back so that it doesnt over-do the initial rev-up. It drains the battery almost dead then will fire up. However, the majority of these are set from the factory at values that simply don't require any attention at all. Quick to respond and very knowledgeable. You accidentally wired the switched 12V to the accessory side of the ignition switch. Beyond that you're going to have to get Holley tech support involved. Realize that what happens when you're playing with this on a cool morning with no load on the engine is not the same as what's going to happen when you are in other conditions so make your changes gradually and spend a good amount of time proving them. Hard starting cool but starts easy when hot. Any help with this would be greatly appreciated.Gary. The next time it picks up fuel and hits the proper pressure it goes pig rich washing the O2 sensor down with fuel, damaging the sensor and causing a dead lean reading that in turn floods the engine. Capability Range: Moderate No throttle press was necessary to perform the start belowtherefore we are skipping Step One: Tuning Cranking Air. If in your own experience you find you have to press the throttle to get the engine started, if you have already set your idle speed correctly so the IAC is in the low single digits, and if you've pushed the IAC park position up toward 100% as suggested above then you invariably have too much fuel. Thanks. Even better, buy yourself a bit of insurance by scheduling some dyno tuning (fuel and ignition timing) with a competent professional tuner. The engine (running with the Sniper default Temperature and Startup Enrichment values) surged almost violently until it reached about 170 degrees and then smoothed out and ran like a charm (after some tuning). In fact, they may be terrible values when applied to your engine. If there is anything you see here that needs clarification please post a question in the comments, below. Increase that to 15 to start. I am running a wet exhaust with O2 sensor plates. Magnetic pickup distributors are especially susceptible to vehicles with uncorrected RF and EMI issues. Goat Rope Garage 76.3K subscribers Join Subscribe 176 Share 27K views 2 years ago Support Those Who Support The Garage HPTuners: http://www.hptuners.com Show. Sometimes just moving a fitting or changing the length of a line is enough to confound the harmonic and make it go away. I really want to go EFI this year. Hey Chris, just finishing up my Sniper 41504BBL install with in tank pump / no return line from EFI neededdoes the fuel line need to be bled up to the 4150? Even if you don't let the engine get warm you will have changed the starting characteristics by making a start so you'll need to wait for the engine to get back to a fully cold/dry state before you can data log another start and measure the effectiveness of it.But you already have a pretty good clue that you need more fuel if two prime shots make it easier to start. Capability Range: Moderate If I start the car cool and dont touch the gas the engine will crank and crank and never fire. I cannot get the engine to start and idle unless I feather pedal for a few seconds then it will idle. However, each engine is different. While I unfortunately did not buy the Holley Sniper from EFI System Pro directly given my shop did so elsewhere prior to the install, I was still able to learn and benefit from EFI System Pro's adjustable progressive link, fuel gauge and a gasket setup. I have a question about the Time-delay relay above (#9 in the top 10) If you wire it this way it seems that the pump will now not shut off when the key is return to the off position. Once engine is warmed up been driving for awhile. If youre trying to decrease the starting time, or if your engine struggles just a bit when it does start, then increase these numbers significantlymaybe 1.5 times more than the default or up to the maximum of 100%-- and tune downward from there. So now youre left with tuning the Fuel Prime Multiplier. Fortunately, Holley has another product that can solve that: Hydramat.. Hydramat is not inexpensive but you won't believe what it can do. How efficient is your engine startup? to the same number as 4.) Part throttle sucking sounds. Ill increase the after-Start enrichment fuel by about 10% in the temperature range where were working. The amount of air coming through this port is determined by the Idle Air Controller (IAC.) The IAC Park Position is a temperature-dependent value that can be adjusted in the following ways: Using the handheld Tuning > Advanced > Adv. So, yea it gonna ALWAYS be hard to start!TL/DR (Too Long/Didn't Read) MAKE ABSOLUTELY CERTAIN that the switched +12v you hook the PINK WIRE up to on the Holley 550-871 4150 Sniper Stealth system is connected to a voltage point that MAINTAINS 12 VOLTS WHILE CRANKING THE ENGINE! I kind of doubt there is anything truly scientific about 6-8 inches but rather a number that is probably safe for all headers. Thanks. Is the sniper compatible with my distributor? Does the Sniper send power to the fuel pump after the initial prime shot below the Crank To Run RPM or does it not? Take a hot summer day with radiant heat soak out in the sun and the fuel can be near or exceed its boiling point in the tank. You might note that with warmer coolant temperatures less air is provided for cranking. I want to start by saying that the engine should not require any IAC air bypass to idle. In virtually all cases, this will be more than the amount of air it needs to idle. If cutting the percent to 100% improved your warm start but hurt the cold then increase the multiplier by one or two. A brief spray of fuel is injected before cranking. my screen recording software i. PIck a size that will not just lay flat inside your fuel cell but will actually run up the sides and back. You should then have at least 18-24 of pipe after the sensor. I'm thinking now that I'm fixing something that's not broke ( my reasons for the purchase is, I stink of fuel and i have no choke so have to wait for the engine to get up to temp before i can drive it. Power glide with 1.80 first gear, 6,200 converter. Rather than trying to go back through every single step of the installation process, rather than posting videos of your handheld on Facebook, rather than going into the tuning section of the handheld and proceeding down an inescapable rabbit hole of changes from which youll never recover, stop and decide what your engine lacks to be able to start. Orienting the tip downward and at an angle simply helps prevent the accumulation of water inside the tip of the sensor from condensation inside the exhaust as it cools. Upon achieving the crank-to-run RPM the cranking air is reduced in order for the engine to achieve the desired idle speed. When a wide band sensor is (DAMAGED) it almost always reads dead lean. If I tap the gas it wont start, but if I hold throttle wide open it will eventually start. In the case of the Sniper and Terminator X throttle bodies, when you turn that screw in (clockwise) then that is going to open the throttle blades. I hope to do more articles similar to this so stay tuned! Im getting ready to instal a sniper master kit on a Ford Oil control: If you're burning oil you will kill your O2 sensor, closed loop chasing unstable fuel supply issues( see fuel pumps comment). Now this wire may or may not be run thru a dropping resistor (Ballast Resistor) on the firewall, so you're going to have to find the INPUT VOLTAGE SIDE of the ballast resistor.Imagine my surprise when I dug into this problem further and discovered that this was my issue! :-). It starts fairly well. Anything else would be a big safety no-no. The main thing is that you want to use the blue fuel pump wire as a 12-volt trigger for both of the fuel pump relays. I still have the lound sucking air sound. Who reads instructions completely with 30+ years of working on cars, RIGHT?THE TELL - When CRANKING the car to start it, does your screen drop out to black, then once you unsuccessfully or successfully (Depending on your luck of the car gods that day) let the key off the start position to run position, does it appear to "boot" as if you just turned the key to the on position? Set the table type to Air/Fuel Ratio Offset4. Not some generic pump as some have speculated. Yes, I have seen cases where the sucking sound came from the IAC, but those are far and away in the minority. Find a lower price anywhere and we'll beat it by 5%! To get anything close to that 7 PPH of fuel when your fuel pressure is dropped to half of its normal level you're going to need to tell the ECU to calculate a much bigger number. If the fuel pressure is a little low don't worry about that. He gave no details, is this an option and how would one go about this. Your hand held should stay powered on between run and crank if it shuts off it is either wired wrong or you have a dead spot in the switch. Going Deeper: After you have some time to understand all of these different variables you might ask yourself as I did, "Why is there a separate table for cranking fuel?" Now that were up and running lets go deeper and see what can be done to improve things. If you do not understand a step seek assistance. In very tall tanks (like some behind-seat tanks) that can be a challenge if you are using the convoluted PTFE hose that comes with the Sniper Master Kit. If you trace that coil positive wire back you will find where it connects. Starts & immediately dies. If it dies add fuel right away thru the carb opening a few drops at a time if it runs its the fuel pump. Most current pump fuels boil around 130 degrees.