New or not i have send dead item right off the shelf. One thing I miss is the instant drop in rpms that my 650DP had. That added fuel is called after-start enrichment. Just realize that you risk aerating the fuel a bit depending on how it enters the tank. Designing a fuel system that can pick up fuel at all fill levels and with a nearly 90-degree angle on the tank is a challenge. 3.) May 23, 2022. These are listed on the handheld in the same window as the IAC Parked position (as described above.) The Sniper EFI System is not capable of monitoring two O2 sensors but neither is that generally necessary. Any suggestions? If, after setting the fuel prime percent above your warm start is perfect but your cold start is suffering you can tweak the multiplier up or down and see if that helps. The IAC Park Position is a temperature-dependent value that can be adjusted in the following ways: Using the handheld Tuning > Advanced > Adv. :-), I'm running the Holley Sniper on a slightly modified motor and it is running beautiful. Capability Range: Moderate Make sure you are using proper wiring practices. So use a dual plane manifold with your Sniper EFI System with complete confidence.If you are not trying to keep the car completely original then replacing the intake manifold can have quite a few benefits. Continues rich and then goes a bit lean. However, each engine is different. My situation, although related to start up, is somewhat different. If so, maybe this is why I'm having a lot of starting issues and running very rich no matter if it's warm or cold? Thanks. (Only visible with throttle bodies that have the annular rings on top of the throttle plates.). Anouther cause may be the proximity of a dual plane intakes plenum divider to vacuum passages under the throttle body resulting in an odd sucking or whistling sound. Looking at the 4500 sniper and I run Super Street 10.90. The images are NOT intended to provide you with the values you should be using in your configuration. That amount of air is determined by the IAC Park Position. I have a sniperstealth witch dui ignition and Holley in tank pump. 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. If it cranks better then you know you're getting too much fuel. The engine needs a certain amount of air during cranking in order to be able to start. I was wondering if you could help out? A low air to fuel ratio means the mixture is rich. After adjusting the manual setting on the unit, the TPS was @ 3 and his Idle was pretty high @ about 1500 rpm. Does it recover if you bump the throttle? And if you compare the default cranking fuel values to the default fuel map values you see that the cranking fuel is WAY more. If so then it is (regardless of what the O2 sensor says.). Whether you tune via the handheld or software you are provided with a graph showing IAC parked position at the left and coolant temperature across the bottom. At the bottom you'll see AE vs TPS RoC Blanking. https://www.msdperformance.com/suppos/#EngineRunOn, If this is your first visit, be sure to Copyright 2017 Cyberspace Automotive Performance, Inc. All Rights Reserved. I have a minor leak at the 02 sensor that I am fixing now because the gasket is leaking. Any help with this would be greatly appreciated.Gary. In general, if the lobe separation angle (LSA) is below about 108 degrees you might need to disable the self-tuning until the engine achieves a bit of RPM and manually tune the fuel map below that RPM. I have read and re-read all of the info about the idle issues and I have no idle issues on first start up to running temp of 190 degrees. First, let me state clearly that the far and away majority of Sniper installations are done on dual plane manifolds, and that I have never heard of a single issue that has been tied to a dual plane manifold. Maybe Holley will add Fuel Prime Multiplier to Terminator X later. Bolt-On EFI for your Cheers Darren. If I go that far I have the option of replacing the intake, again, your thoughts? If you're installing a Sniper EFI system and almost ready to crank it over for the first time, this is the video for you! "I've edited the article with a note about the difference. Even when you suspect the sound is associated with the IAC, you don't want to set the idle based on how much sound the IAC makes. If you . All seemed well with the setup and going through the handheld. Holley knows how to do math! Troubleshooting - engine starts and stalls Troubleshooting - engine starts and stalls Bill Tichenor 12/02/2009 10 min read Share Carburetor Installation and Tuning Video carburetor tuning and adjustments video Footage taken from Holley Carburetor Installation & Tuning DVD author Bill Tichenor 358 Posts An Article About Not much I can add to that. O2 Sensor Mounting: The O2 needs to be mounted 6-8 after the merge in the header collector. Not perfect but not bad. Holley Sniper EFI--Look, No ECU or Wiring Harness! Maybe I am missing something here. Thats what we want, right? I really want to go EFI this year. Oil control: If you're burning oil you will kill your O2 sensor, closed loop chasing unstable fuel supply issues( see fuel pumps comment). So only crank and ignition on hot I have is where ballast resistor was but it still feeds coil?Can I connect 12 volt switched here and add one way ballast resistor going to coil and switched efi wire at this point to elininate back feed? Question is, do I just plug what was the return at the throttle body? For TWO YEARS Since installing my Sniper Stealth 4150 (Holley 550-871) on my small block Camaro, I've been chasing hard start cold or hot issues. Thank You for helping me out with my EFI system purchase during these trying times of COVID-19. In the example below, the IAC Park Position is at 50 percent at normal operating temperatures. Go Gators. 2023 HOLLEY PERFORMANCE PRODUCTS, INC. ALL RIGHTS RESERVED. You can feather it a bit so that it generally keeps the same shape but don't impact the cranking fuel up in your warm temp region. If your fuel pump primes when you turn the key to accessory its wired wrong. In my experience startup fuel tends to be too much. These settings will be instrumental to a fast start. ), Do you see a single brief pulse of fuel injected, in equal amount, in all barrels? We can adjust that with the after-Start enrichmentIll bump that up a bit. Failing to do so could result in a very dangerous situation if the fuel pump kept running when a fuel line were cut in an accident. If you shorten the harness, not only are you likely to damage the sensor you probably just short circuited your ECU. Capability Range: Advanced 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. Is the fuel pressure correct? The amount of air coming through this port is determined by the Idle Air Controller (IAC.) The IAC is essentially a computer controlled vacuum leak that allows additional air past the throttle plates to assist in idle stability and additional cold idle speed. Whats the fix? Why? Unfortunately, the only way to do this is with the Sniper Software. I call this the Happy Dance moment. Sounds like it is "only" burning through the initial priming shot. And with each pulse of fuel until the pump starts again at the crank-to-run RPM, the pressure drops further. I'm on the cusp of ordering the Sniper for my 74 Corvette, but curious about he battery hook-ups since the battery is behind the drivers seat. Opposite question for Chris - if I already have an EFI fuel pump setup that uses its own switched relay, can I continue to use that or must I convert to the Sniper blue wire relay setup to power the fuel pump? Full product line and accessories at excellent pricing. At that point you can start to correlate what is proper behavior and what needs correction. This happens with some carburetors on dual planes as well. This Mr. Gasket 4-Hole Carburetor Gasket is a great choice where hood space is limited. I have it disconnected to flush any debris out.Thank you. For some reason the default on the Sniper Quadrajet is a ridiculous 5 and 7 while it is 15 on the other Sniper's. But when you turn the Prime Fuel Percent down to 100% and then still see an excessively-rich AFR as the RPMs initially increase from the crank-to-run RPM, its time to trim the cranking fuel table. But what if it doesnt? How efficient is your engine startup? The Ordering process was so easy and non-painful. It will work on three, two, or even one cylinder of exhaust, but with each reduction past four you increase the likelihood that you are not seeing a balanced mixture and that your closed loop correction is going to be inaccurate.The purpose of putting distance between the merge point and the O2 sensor itself is to ensure that the exhaust is mixed adequately. Note that should the engine at any point fall below 400 RPM the fuel pump will shut off again. *Possible delays due to Covid-19 click for more information. Air is not just coming into the engine via the throttle blades. It will come back up when the engine is running.If you have fuel pressure then you've got to dig deeper. Set the table type to Air/Fuel Ratio Offset4. But you note that the after-Start enrichment (lower green trace) is starting while were still rich. It worked fine with carb, hope someone can help. Beyond that you can turn your cranking fuel down. But I have MSD 6 AL. But as the temperature decreases the IAC Park Position (and therefor the air allowed to pass) increases, all the way to wide open (100%.). Thank you for your ongoing support. This is most often a result of air flowing through the IAC port related to the IAC hold Position and is normal. Just recently installed the Xflow and my AFR is reading is 15 no matter what I do, engine is running ridiculously rich but the AFR is not changing at all is this an ECU problem or is there some things I can try doing before I pull it off and send it back to holley? Resistance results in heat and heat results in more resistance. First, it is fake news that EFI doesn't like big cams. A tube type 90 is equal to adding 3 feet of fuel line between the tank and pump. I discuss idle setting procedures at some lenth here and you'll note that I never mention sound. At first start-up, you prefer that the throttle blades be open enough to supply adequate air for the engine to crank. And the less correction you do until you understand that---the better! Run the switched 12-volt back as close to the ignition as possible. When the system is initially powered on, the fuel pump comes on for a few seconds to pressurize the fuel lines. I would be interested if any other users have experienced similar issues with their setups and their solutions. Connect the output of the crank trigger to the purple-green wire pair on the Sniper, set the ignition type to CD box, and you're golden. This, in turn, will power the Sniper. 4.) Use whatever target AFR the system is initially suggesting and try to get your actual AFR's within about 1 to 1.5 of that value. 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. Any tips or info on cold starts? Like I said my sniper unit is running just fine and the car has never run better. Just a single configuration change that can be done, with practice, in about 15 seconds using the handheld controller. Default values on these are 150% and 5, respectively. Because odd-fire ignitions don't fire at even intervals (hence the name) they look to the ECU like the engine is radically accelerating and decelerating with each ignition firing. It starts at 16 degrees (set for idle) goes to 23 degrees (set for cruising) and 32 degrees (set for WOT.) Are you running timing control? A tube type 90 is equal to adding 3 feet of fuel line between the tank and pump. 12/02/2009. A common issue we see is a result of poor fuel pump grounding running a eyelet from the pump ground to a rusty or painted surface. I've never seen the shop I had install my Sniper hook up a lap top to the car. Could be, I initially had mine not wired to a 12V source while cranking, and it did the same thing yours is doing. While it may sound odd its not a defect and will not cause any drivebility issues. Stay up to date with the latest releases, events, promotions and more. 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. Seems like thats what its doing. Copyright 2017 Cyberspace Automotive Performance, Inc. All Rights Reserved. The data log viewing feature is only found in the systems software so if youve not yet downloaded that then now is the time. May God's grace bless you in the Lord Jesus Christ. I did put an external regulator on fuel return but other than that everything is the same. Do you see an issue with this? While continuing to observe the barrels, crank the engine. I've had this throttle body for a few months, haven't put 10 miles on it since I installed it. If you turn the ignition off and back on, & crank it, it will start & die again. This page was generated at 05:08 PM. Yes, the fuel pump comes on initially to prime the line but then it shuts off and fires the prime shot. 2.) Don't be that guy. From there it is a slam dunk. All times are GMT-6. Never use the yellow wire if you're running a CD box like an MSD 6.The 1/4-inch line should not be used as a return. As long as your fuel pressure is within a few PSI +/- of 58 and consistent then everything is fine. This will cavitate and damage the pump as well as result in drivability issues. More or less how do I build a timing curve?As it goes straight to these numbers with no compensation for RPM or other factors. Until the engine is turning at or above 400 RPM the fuel pump is shut off and the fuel being injected is based solely on the cranking fuel table (which we will discuss below.) 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). Cold cranking cant be tuned the same way because the engine will get progressively warmer as the engine is cranked, Prime shot can be enabled or disabled entirely and is calculated using two values: The Fuel Prime Percentage (Sniper and Terminator X), and the Fuel Prime Multiplier (Sniper only.) But weve also introduced some leanness from 4-10 seconds. So try cutting both of those numbers in half and see what happens. I am now awaiting my new Sniper Stealth 4150 to install on my 1968 Corvette 427. Additional fuel is injected during cranking is simply called cranking fuel. Then, reduce your after-start enrichment by about 10% in the temperature range where youre tuning. Am i doing the right thing? Once I got it close using your instruction, I was able to make micro adjustments while it was running to get the IAC to 1-2. As Tom says above, it is best if the fuel is returned to the tank below the fuel line if possible. Avoid using any 90 degree fittings between the tank and pump. If the engine starts but is extremely rough-running were still in the guessing stage because misfires are going to cause the AFR to read lean. You have that where you want it. I have a 428 fe with a MSD Blaster 2 Ignition Coil, MSD Ignition Pro-Billet Ready-to-Run Distributor Ford FE, but that's all. Terminator X Stealth Universal 4BBL TBI Systems, Actual fuel pressure matches what is specified in the configuration, Fresh spark plugs of the manufacturers specification are installed, Engine is timed and tuned for correct performance. Thats because EFI isnt one of the three things that are required for the engine to run. It appears to be in throttle body? Disable the tach sweep on your ignition box. Enjoy! The Sniper ships with an OEM grade Bosch O2 sensor. When a wide band sensor is (DAMAGED) it almost always reads dead lean. Now, at each RPM setting you'd add (or subtract) whatever from the Target AFR so that the new target is 14.0:1. Price Point: $$$. 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? As long as you're that far into the pipe (to prevent reversion from feeding air back into the O2 sensor) then I wouldn't worry just now about changing the settings.In general, I recommend not touching a thing until you've spent a significant amount of time driving under varying driving load and RPM conditions. Find a lower price anywhere and we'll beat it by 5%! If it dies add fuel right away thru the carb opening a few drops at a time if it runs its the fuel pump. Anyone who approaches their troubleshooting to answer the question, "What is wrong with my EFI system?" Is the sniper compatible with my distributor? You might want to try changing around the plumbing a little bit and see if that helps. Don't let that get the best of you. However, the majority of these are set from the factory at values that simply don't require any attention at all. All of these values are configurable. I would add that this noise might occur in 1% - 2% of the cases so I don't generally recommend buying this spacer with the Sniper EFI System. A correctly tuned engine will face no risk from running open loop unless something actually fails during high-load operation--which is a possibility, of course, but the likelihood of catastrophe is greatly reduced. Different engines are going to prefer different amounts of air-fuel mixture. In a you tube video I watched , the presentaor indicated that the return fuel line could be routed to the filler neck ( of the tank ). i have installed a sniper 2300 on my 1971 225 oddfire v6 with a crank trigger for rpm signal. Anything else would be a big safety no-no. Probably 3-4 seconds, and rich after it does fire. 02/23/2023. What do I need to do to rectify this issue? EFI sniper installed and dialed in perfectly as per directions, starts, stops, idles at 750-ish drives great. to zero, but I think you'll find that you will stall. Price Point: $$, EFI Systems based on Holley's world-class Dominator and HP ECU's. Idle and cruise can be tuned leaner with "seat of the pants" feel. Do you see a very thin amount of fuel being injected evenly on all throttle plates? Will the height of the return line be an issue? Quick to respond and very knowledgeable. MSD recommends non resistor plugs. Only thing I have done since last Wednesday was add Holley EFI gauges. I am in the middle of plumbing my new sniper throttle body system. A brief spray of fuel is injected before cranking. You're not running your EFI system without a gauge are you? There is really no room for error on this. I'm trying to get this article done. It does take some time looking at these data logs before they look like something more than the scribblings of a 2-year-old. But never ever forget there is a second learning going on--your own. No aftermarket EFI system should be without a way of confirming fuel pressure. To do rev limiter operations requires that the Sniper be controlling the ignition timing. check out the. I have a datalog. Ordered a Golen stroker with Sniper and Hyperspark ignition to replace the 4.2 in my 89. Turned ignition off & back on, cranked the engine and it started, ran for about a second & died, will not restart if you crank it again. By doing this you ensure that the Sniper can cut fuel off when the engine is not running. Super helpful. Price Point: $, Advanced throttle body A coolant temperature enrichment factor will be applied if the engine is not up to operating temperature but a bit more fuel is normally beneficial as well. You see that the AFR trace is ar below the target AFR (pink trace.) It connects the Sniper switched power to a very "dirty" power source. Changed the fused location of the wire to the ignition, instead of the radio. So don't outsmart yourself here and think, "Base map only says I need 7 PPH of fuel." (Ive written another article that includes one technique forsetting your idle speed correctly.) The resulting resistance can burn up fuel pumps, wiring and relays. You should then have at least 18-24 of pipe after the sensor. Good luck! Fix that.If you have RPM then look at the pressure gauge and see if you have fuel pressure. Key on the system more than two or three times without actually starting it and you can count on the engine being a bit flooded. Feed pressure should be knocking on 58 PSI and the return should ideally be zero, if the feed pressure is not correct, or if the return line pressure is greater than 4-5 PSI find and correct the restriction before proceeding. Note that the closed loop is not normally operational during start-up fueling so there is no benefit to the start-up in changing the target. Try cranking immediately upon key-on--before it has a chance to prime. Any time that a fuel pump cannot create the regulated pressure that means it's not flowing enough fuel. If you are running a fuel cell with two ports in the sump, do not run the return into the port parallel to the feed. 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. And it may have improvedor it may have gotten worse. Several things to cover here. Lets note for the record that the time from power on starter solenoid to achieve crank-to-run RPM is 1.13 seconds. Not some generic piece as some have speculated. How do you set this up?Thanks! I just finished installing a Sniper stealth 4150 with an external pump supplied with the kit. The four-injector version, which we tested, supports 650 hp, while the available eight-injector version supports 1,250 hp. I figured it would be minimal. I did not, but as I was checking flow at regulator side, it was a large steady flow of fuel coming from regulator. Thanks. Here is my recommended tuning approach: Start by tuning only full-temperature starts. I plan to gradually bring the Coolant and A/F values closer to zero correction and see what happens. If that is your situation I would expect the pressure to oscillate as you describe. Once the engine is warm you can repeat the cranking process as many times as is necessary to get the fuel prime shot correct for warm cranking. You just have to go one direction and see if things improve or not. 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. Then, click on AE vs MAP Rate of Change and change that to 15 as well.
Crosley Record Player Troubleshooting, Articles H