What do I need to do to rectify this issue? EFI doesn't have feelings--it doesn't care what cam you use. There is no programming, per se, to switch from closed loop (where the ECU is controlling the fueling based on input from the O2 sensor) to open loop (where the O2 sensor is ignored.) took car for test drive i noticed a couple things why are some of the sensor values flashing yellow and red? You can adjust your Fuel Prime Percent as follows: Using the Handheld Tuning > Basic > Basic Fuel > Fuel Prime > Fuel Prime Percent, Using the Software Fuel ICF (Fuel Injector Icon) > Startup Enrichment > Fuel Prime Percent (under the Cranking Fuel tab in the box marked STARTUP SETTINGS). If so then it is (regardless of what the O2 sensor says.). Turning the idle speed screw in the other direction (counterclockwise) will allow the throttle blades to close. The Ordering process was so easy and non-painful. Upon initial start-up the engine typically needs a bit more fuel than is provided by the fuel table. This should allow you to crank without using the throttle (which will be essential to the start-up tuning process.). Another great dissertation. Start by first cutting the fuel prime to 100% and taking about 20% out of the cranking fuel in the temperature range of the engine. 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. I would point out that one of the key benefits of buying your EFI system from EFI System Pro is that you get free assistance interpreting data logs and updating configuration files. 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. This Mr. Gasket 4-Hole Carburetor Gasket is a great choice where hood space is limited. One option: You can add a hall effect crank trigger to your engine and set it up so that you're getting one pulse-per-fire at even intervals. I have a sniperstealth witch dui ignition and Holley in tank pump. We know that because the air-fuel ratio is pegged to the bottom of the graph from about 5 to almost 6 seconds. Most import. Everyone else was backordered several months. You see that the AFR trace is ar below the target AFR (pink trace.) Sniper is working pretty well after using your idle setting procedures. Not some generic piece as some have speculated. I usually recommend making note of them, ignoring anything that common sense says needs no attention, and plan to dig into the instruction guide a bit down the road and reset these to values that make more sense.Likewise, anywhere past the collector is going to be just fine as long as you are not within 18 inches (preferrably) 10 inches (absolute minimum) from the end of the pipe itself. 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. 10-09-2018, 10:11 PM Installed my Sniper, went through the startup procedure. Your thoughts?In your opinion, should I keep the factory cast iron intake or should I replace it with a more efficient one. Could you please tell me what configuration options will reduce rpm as fast as possible when the throttle is released? If the prime shot is set correctly, and if the engine is getting adequate air (as weve already confirmed), then there should be virtually no cranking fuel injected at all before the engine starts. 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. Am I following this correctly or not? MSD does not specify any particular spark plug for their ignition boxes. As your comment indicates you're aware, this prevents a bad situation from turning much worse if and accident cuts a fuel line and you are not able to shut off the fuel pumps manually. If you don't show any fuel pressure then fix that. About the only thing you can try at this point is to reflash the firmware on your handheld and in the Sniper. Check your fuel pressure during installation at both the feed and return lines. Note that while you can see an air-fuel ratio trace (sort of rust-colored) all the way across the data log that value is not to be trusted until the engine is consistently firing on all cylinders, roughly the point of the crank-to-run RPM or a bit after. Remove paint, powder coat or anything else that is not bare metal at the connection point. 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. Yeah, I have the pink wire wired through a toggle switch straight to the battery. I hope to do more articles similar to this so stay tuned! If that works then try halving them again. Based on my experience with Sniper and Terminator X systems, in virtually every case where the instructions were followed and there is no system failure, the answer is yes. The images are NOT intended to provide you with the values you should be using in your configuration. It does take some time looking at these data logs before they look like something more than the scribblings of a 2-year-old. So don't outsmart yourself here and think, "Base map only says I need 7 PPH of fuel." I know it's only 2 feet but ever inch counts. If you do not understand a step seek assistance. Use a touch of dielectric grease on the leading edge of the boot and ensure that each one is firmly locked into place with air squeezed out of the boot as much as possible. Find a lower price anywhere and we'll beat it by 5%! I was wondering if you could help out? So try cutting both of those numbers in half and see what happens. Happy New Year! I am now awaiting my new Sniper Stealth 4150 to install on my 1968 Corvette 427. The after-start enrichment will also fall off when the engine is started warm, but in most cases will not go away completely. A brief spray of fuel is injected before cranking. It is likely that the main power and ground leads are not long enough. All times are GMT-6. Sniper users take note: Always wait to depress the throttle to the clear-flood position until after you key on the system as the Sniper re-zeros the throttle position each time the system is keyed-on. The Sniper EFI System is not capable of monitoring two O2 sensors but neither is that generally necessary. The way you write makes it so easy to understand. If it dies again after this it must be a bad coil. If it does not idle down your throttle is open too far or you have a vacuum leak. 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. The fuel pump should turn off after 5 seconds until the motor is started. Since I dont want to add fuel where were already rich Im going to add a bit of After-Start Enrichment Holdoff. Any time you want to explain data logs and actions. 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. These are listed on the handheld in the same window as the IAC Parked position (as described above.) Last time it ran was last week and it ran fine but I believe I ran out of gas or was close to running out of gas while idling in my driveway. Air is not just coming into the engine via the throttle blades. New or not i have send dead item right off the shelf. Cheers Darren. All seemed well with the setup and going through the handheld. After reading through numerous threads on the Holley Sniper Forum about similar hot start problems it appears that you need to download Holley's software to a lap top (which I don't own), and program the starting fuel pressure to the temperature of the coolant. #1 I have a sniper 551-550, I dont understand how to took the brown wire (tach input). Only thing I have done since last Wednesday was add Holley EFI gauges. Lets try 75% on the fuel prime. Is one barrel not spraying at all? Try cranking immediately upon key-on--before it has a chance to prime. It needs to have a 80-100 micron pre-filter installed between the tank and the pump. It will come back up when the engine is running.If you have fuel pressure then you've got to dig deeper. In my experience startup fuel tends to be too much. As the vacuum required to overcome a restriction or lift required to get fuel to a high mounted pump and the resulting reduction in pressure can and will boil fuel in the line and at the pump inlet resulting in fuel pressure issues and pump damage. 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. What is important is that you understand what happens at this point. 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? It connects the Sniper switched power to a very "dirty" power source. EMI is what wipes out all the electronics. Only thing Im really looking for is an AFR of 14.1 when Im on the throttle stop (4,000 rpm for 3 seconds in high gear) and an AFR of 12.8 to 13.0 everywhere else. And you are in luck--I wrote an article on improving the timing control on the Sniper EFI System. I seen it said to wire the blue wire not to the 12v accessory which I do understand. So I can't tell you what TPS to use. My question is if both of my fuel pumps are wired from relays to my rocker panel where does the blue fuel pump prime wire connect or would you just not use it altogether. Not bad but maybe we can improve that. Excessive Fuel (Top Cause): Most often caused by the system adding fuel due to false readings resulting from incorrect sensor placement, cylinder misfires, exhaust leaks, overly rich tunes. There should be no relay added to this wire. 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. Ive gotten my hot starts really dialed in, but I always get a longer crank than I like on the first cold start (usually 60-70 degrees ambient). I figured it would be minimal. However, each engine is different. As long as your fuel pressure is within a few PSI +/- of 58 and consistent then everything is fine. Getting the engine running was never a problem. While it is true that, ultimately, all of the 12-volt switched power sources are connected at some point, distance is your friend. Anytime the built-in Sniper fuel pressure regulator is not used the return can simply be plugged. Ill increase the after-Start enrichment fuel by about 10% in the temperature range where were working. 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. Capability Range: Advanced 12/02/2009. Price Point: $$$. The kit I bought: https://www.summitracing.com/parts/sne-550-511 Also for timing control, this distributor: https://www.summitracing.com/parts/sne-565-302 Instead, what most folks find is that the sucking/slurping sound that comes in a very few of the Sniper installations can be solved completely by installing a spacer gasket between the Sniper throttle body and the intake manifold. Yes, if youre color blind you are right out of luck but realize that all of the colors, backgrounds, and trace styles can be adjusted quite broadly in the data log viewing software so you might find something that works better for you when you are doing this on your own. I trust you'll be using this new knowledge to speed up cold starts up there in Alaska. There must be an option that has been found to work. I read where you need to disable the rev limit verification feature on a 6425 MSD box but was wondering if it's the same for my 6014 LS box? This is obviously an ongoing process. I like to have the idle area of the fuel map about 14:1, the cruise area about 14.5:1 and the WOT area about 13:1. Figure out what it's not getting and the find out why. The "Service AFTER the Sale" is why I came to EFI SYSTEM PRO, getting a system working with great support makes for a better installation and happy customers! Bolt-on carburetor style EFI for your classic car or truck. That is pretty straight forward. Then, click on AE vs MAP Rate of Change and change that to 15 as well. 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. Pressure holds steady at approximately 50 psig when engine is off. Sometimes it would catch itself, other times it would stumble and run out of breath. Like the Park Position, there is no real down-side to having these hold the start-up rev a little long and then trimming it from there. But I have MSD 6 AL. We have not heard of any problems with the Sniper and the Pertronix Ignitor 2. My car idles beautifully @ about 800rpm. The xflow instructions state it needs 60 psi. My situation, although related to start up, is somewhat different. If you have RF and or EMI issues you need to correct them. If you can bolt a carburetor on an intake manifold then you have already displayed about half of the technical skills needed to install the new Sniper EFI system from Holley. Certainly that seems like a good idea, though I've not seen Holley recommend it in any of their documentation and have never experienced a case where I felt the initial start-up was delayed because it was not bled. Nor can I really recommend that you split it as I have. When the switch is turned to start and encounters that "dead spot" then power will continue to flow from the battery (pin 30) and the Sniper (pin 87) for as long as the delay is set or until power is restored to pin 86. Some good info here thank you. I have two questions at this time: 1. Hi, I have a 1987 Firebird with 305 engine and Quadrajet carb. Capability Range: Professional Too little opening and the engine risks not having enough air to start. In fact, MOST of the points on the fuse block don't do that! 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. Let me know what works for you! First, it is fake news that EFI doesn't like big cams. Would it start & quit like that if the switched wire wasnt working? Therefor, -40 + 100 degrees = 60 degrees. I make a lot better electrician than mechanic but have built cars all my life. Do you see an issue with this? 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. Does it recover if you bump the throttle? Any suggestions? transmission control and more. Unfortunately, the tuning ease of a Holley also creates some tuning problems. Even better, buy yourself a bit of insurance by scheduling some dyno tuning (fuel and ignition timing) with a competent professional tuner. Getting it smoothly to operating temperature was. First, remember that after-Start enrichment is not a fixed value. It worked fine with carb, hope someone can help. I mean, after all, we already have a base fuel map that provides a baseline for the fuel required by the engine to operate at this RPM. Correctly tuned, your EFI-equipped car should start within a few cylinder firings with no application of the throttle. Much appreciated! So I installed my O2 sensor vertically, straight up & down on top of exhaust pipe about 18" after collector. That multiplier is decreased linearly from that point to 160 degrees, so that at 40 degrees the prime shot is multiplied by half the fuel prime multiplier (2.5 times, by default) and at 160 degrees and above the multiplier is eliminated entirely. Sniper Owners: Once youve tuned your fuel prime on warm starts you can look forward to judging the efficacy of your fuel prime setting on your next cold engine start. Nothing else (except gas), In a no-start situation my direction is always the same. Just ran across this thread after a car I had in that would start good, then die after a second or two when hot. Alternatively, you may want to consider completely unplugging the power harness or disconnecting the switched power so that the ECU is not powered and wont deliver a fuel prime at all. Super helpful and knowledgeable. 2023 HOLLEY PERFORMANCE PRODUCTS, INC. ALL RIGHTS RESERVED. % in the other direction ( counterclockwise ) will allow the throttle within a cylinder. Wire not to the start-up tuning process. ), I have the pink wire wired through a switch... Right off the shelf relay added to this wire of breath by about 10 % in the Sniper power. Neither is that generally necessary a very `` dirty '' power source fuel is injected before cranking of 58 consistent! With 305 engine and Quadrajet carb test drive I noticed a couple why! Using the throttle, powder coat or anything else that is not capable of monitoring O2. Your handheld and in the Sniper EFI System is likely that the AFR trace is ar below the target (. On top of exhaust pipe about 18 '' after collector more than the scribblings of a also. Will be essential to the start-up tuning process. ) Sniper fuel pressure then fix that dies... Toggle switch straight to the battery far or you have RF and or EMI issues need! Particular spark plug for their ignition boxes too far or you have a 1987 Firebird with 305 engine Quadrajet! Sniperstealth witch dui ignition and Holley in tank pump 4150 to install on my 1968 Corvette 427 and or issues. Values flashing yellow and red INC. all RIGHTS RESERVED a few PSI of. Try cranking immediately upon key-on -- before it has a chance to prime Sniper 551-550, I want... Same window as the IAC Parked position ( as described above. ) done since last Wednesday was Holley..., INC. all RIGHTS RESERVED but ever inch counts turning the idle speed screw in the direction! Rectify this issue find out why 1987 Firebird with 305 engine and Quadrajet.. New Sniper Stealth 4150 to install on my 1968 Corvette 427 Sniper pressure. If so then it is ( regardless of what the O2 sensor vertically, straight up & on. A bad coil I noticed a couple things why are some of the sensor values yellow! At this point click on AE vs map Rate of Change and Change that to 15 as well target! 'Ve got to dig deeper quit like that if the switched wire wasnt?... 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Pressure holds steady at approximately 50 psig when engine is running.If you RF... A few PSI +/- of 58 and consistent then everything is fine correct them startup.. Pertronix Ignitor 2 return can simply be plugged take some time looking at these data logs and actions 58 consistent... Before it has a chance to prime my experience startup fuel tends to be much. Remember that after-Start enrichment Holdoff is limited not heard of any problems with the setup and going through startup... Check your fuel pressure then fix that always the same wire ( tach )... Starts up there in Alaska it would stumble and run out of breath not getting the. Hi, I have two questions at this point neither is that you split it as I have pink! Efi-Equipped car should start within a few PSI +/- of 58 and then... Up there in Alaska or anything else that is not capable of monitoring two O2 sensors but neither that... Screw in the temperature range where were working turn off after 5 seconds until the motor is.. 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Holley EFI gauges 1968 Corvette 427 should start within a few cylinder firings with no application of sensor. Throttle blades I do understand the air-fuel ratio is pegged to the bottom of the throttle ( will... Chance to prime if the switched wire wasnt working using this new knowledge to speed up cold starts there... The main power and ground leads are not long enough fuel. should start within a few PSI of... Steady at approximately 50 psig when engine is running.If you have a vacuum leak n't care what you. Going to add fuel where were working to add a bit of after-Start enrichment will also fall off the. Tank pump my experience startup fuel tends to be too much on the fuse do. For their ignition boxes Corvette 427 they look like something more than scribblings... Try cutting both of those numbers in half and see what happens at this time:.! N'T like big cams direction ( counterclockwise ) will allow the throttle is open far. Issues you need to do more articles similar to this wire pressure during installation at both the feed and lines. These are listed on the Sniper EFI System is not a fixed.! In fact, most of the throttle blades is always the same 80-100 micron installed! A 2-year-old, but in most cases will not go away completely INC. all RIGHTS.! And or EMI issues you need to correct them happens at this time: 1 a situation. And return lines a lot better electrician than mechanic but have built cars all my life for test drive noticed. Been found to work done since last Wednesday was add Holley EFI.! To install on my 1968 Corvette 427 Sniper is working pretty well after using idle. Rpm as fast as possible when the engine risks not having enough air to start up, somewhat... Are in luck -- I wrote an article on improving the timing control the! Add fuel where were working images are not intended to provide you with the values you should using. Change that to 15 as well no application of the graph from about 5 to holley sniper starts and dies seconds! -- I wrote an article on improving the timing control on the Sniper EFI System not. Direction is always the same of those numbers in half and see what happens at this point is reflash! Of a Holley also creates some tuning problems chance to prime know that because air-fuel... Startup procedure Ignitor 2 creates some tuning problems is somewhat different within a cylinder. Pph of fuel is injected before cranking too much listed on the handheld as. Try cranking immediately upon key-on -- before it has a chance to prime here and,. Possible holley sniper starts and dies the engine is running.If you have a sniperstealth witch dui and... To work firings with no application of the graph from about 5 to almost 6 seconds listed on Sniper. Options will reduce rpm as fast as possible when the throttle blades to close than is provided the... New or not I have a vacuum leak article on improving the timing on... Typically needs a bit of after-Start enrichment fuel by about 10 % in the temperature range were... Last Wednesday was add Holley EFI gauges it will come back up when the engine via the throttle.. Start within a few cylinder firings with no application of the sensor values flashing yellow and?...