holley sniper starts and dies

I really want to go EFI this year. 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. So do I leave well enough alone or do I try to eliminate the sucking air sound? Whats the fix? That article is actually written by Holley's Tom Kise but I'll be glad to help on it. I feel I could then use the Startup Enrichment parameters (After Start Enrichment and Decay Rate) to fine tune from there. I need to get an answer to the question concerning the TPS. If so then it is (regardless of what the O2 sensor says.). There is a correct setting for the idle and it sound should not be a consideration. Do you see a very thin amount of fuel being injected evenly on all throttle plates? You may have a pinched injector signal wire that has the injector on permanently. Also there are times when I am working on the car, I have the battery disconnected. I kind of doubt there is anything truly scientific about 6-8 inches but rather a number that is probably safe for all headers. (Plus, it's easy to do---see this article.) I plan to gradually bring the Coolant and A/F values closer to zero correction and see what happens. We always recommend that you allow the Sniper to turn the fuel pump off when the engine is not running. Price Point: $$, EFI Systems based on But as you go farther back, it only gets better. They will result in drivability issues, including idle control problems, and could possibly damage the ECU. Bradley Iger. It is likely that the main power and ground leads are not long enough. Because that is very repeatable. I want to run an under the carb type throttle stop. Getting it smoothly to operating temperature was. 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 Sometimes it would catch itself, other times it would stumble and run out of breath. Nothing else (except gas), In a no-start situation my direction is always the same. Thanks Chris for the quick reply, I have already installed a spacer, part # Aluminum Carburetor Spacers SUM-G141. I have a relatively restrictive 2 " exhaust after the headers, due to the through frame exhaust situation. Most import. That is pretty straight forward. Need to add fuel pump for required pressure. I saw a video about this issue and he was able to resolve this issue by adjusting the manual set screw on the unit. The x-axis is time, but it is true that the volume of both after-start and coolant enrichment is determined based on temperature (and certainly that temperature will increase as the engine runs, eventually eliminating any coolant modifier/enrichment.) If you jump in the car, insert the key and in the same move start cranking, you will not get a fuel prime. How did you install the return line to the tank? To do rev limiter operations requires that the Sniper be controlling the ignition timing. 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. So go forward with your install confident with the knowledge that if you need help, EFI System Pro can provide it. I just moved it to the ignition terminal on the fuse block and voila, it ran. :-), Can you show how do you wire up the Delcity time delay relay (#74985) for use with the efi ignition dead spot. You'll note that the pressure drops at that point. We offer two potential solutions. 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. Yes, ensure the Sniper EFI switched +12V pink wire is powered in the "Run". Nor can I really recommend that you split it as I have. If you're tuning a Sniper increase your multiplier and see how that affects you. This should allow you to crank without using the throttle (which will be essential to the start-up tuning process.). Another great dissertation. I have purchased two sniper EFI with the MSD distributor kit. We know that because the air-fuel ratio is pegged to the bottom of the graph from about 5 to almost 6 seconds. 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. You will begin to notice when the system is in closed or open loop, what the target and actual AFR are, and when it is running right or running rich. Capability Range: Advanced EMI is what wipes out all the electronics. took car for test drive i noticed a couple things why are some of the sensor values flashing yellow and red? Part throttle sucking sounds. But few have a crimper that is capable of executing a truly excellent crimp. The clocking of the O2 sensor is not a go / no-go situation as far as the operation of the EFI system. 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! This value can be changed using either the handheld or the software but I am not familiar with a case where changing the crank-to-run RPM has been beneficial. 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. One of the most common causes of poor idle is improper O2 sensor placement or trying to run closed loop at idle with a cam that exhibits quite a bit of overlap at low RPM. I was able to help another fellow with this problem one I figured out that he ran his fuel pump feed to the return-side of his Sniper. Ill increase the after-Start enrichment fuel by about 10% in the temperature range where were working. Price Point: $$$. I suspect that your ignition sense wire from your Holley system is connected to the crank wire that is hot during cranking and shuts off after you let up on the key. Apr 2, 2020 First off thanks to everyone who has been helping me get this thing running. The pump needs to be GRAVITY FED, meaning the pump inlet needs to be at or below the bottom of the tank and as close to the tank as possible. Holley Sniper First Start. Does it matter if O2 sensor goes in drivers side with true duals?Thanks for spending your time helping us weekend mechanics. That is sort of a long shot but more-and-more I have folks give that a try because sometimes it corrects mystery problems that don't have any other explanation. Trying a different mounting gasket configuration of lowering the divider can change the air flow and quiet this down if it occurs. That amount of air is determined by the IAC Park Position. Capability Range: Moderate i have installed a sniper 2300 on my 1971 225 oddfire v6 with a crank trigger for rpm signal. 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. multi-port EFI systems Can I lower it for this purpose? Do you have fuel pressure? You will use the yellow wire to the tach output on the distributor (where the tachometer was formerly connected.) Unfortunately, I know NOTHING about throttle stops. With the engine at full operating temperature you should be able to stick your finger in the IAC inlet port on top of the throttle body and the engine should simply idle down about 50 RPM below your programmed idle speed. Footage taken from Holley Carburetor Installation & Tuning DVD Winter Blowout Sale - Up To 86% Off . But as the temperature decreases the IAC Park Position (and therefor the air allowed to pass) increases, all the way to wide open (100%.). If you do not disable it you will fight startup issues, flood the engine and damage your O2 sensor. 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 did not, but as I was checking flow at regulator side, it was a large steady flow of fuel coming from regulator. The data log shows it getting too much fuel either in the prime shot or the cranking fuel. Can I get ready made tunes?Even with this problem it is by far the best fuel system I have owned. Love the example at the end. It needs air-fuel blend (in appropriate ratio), compression, and spark (correctly timed). Do you have issues with cold start that go away with warm start, or vice versa? If not then stop and buy one now. It connects the Sniper switched power to a very "dirty" power source. If it cranks better then you know you're getting too much fuel. Some good info here thank you. RPM Above Idle to Re-Enable Idle Control.You could simply drop 2.) I've gone through all the steps and cannot seem to solve the problem. Top 10 Sniper EFI Installation Tips from Holley's Tom Kise, Quickfuel 4-hole 1/2-inch Phenolic Spacer. 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. This is most easily done using the blue fuel pump wire. Robust, feature-rich multi-port EFI systems offer easy plug-and-play late-model V8 engine swaps. Unless it is easy for you to do so, or unless you start eating through sensors on a continual basis, I probably would not recommend you changing the clocking of the O2 sensor at this point. Super helpful and knowledgeable. Second is the fact that there are three things that you are adjusting here: Prime shot, cranking fuel, and after-Start enrichment. 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? This is a bit tricky. it runs well at part throttle but at wide open throttle the engine has very little power and backfires.where do i go from here. Will going further help more? Ill check the coil and see if anything else is attached. 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%! But you can take the same steps to adjust the temperature-dependent variables in the cold ranges when the engine is cold. But I can tell you that it is possible to use a switched input to activate a 1-Dimensional Advanced Table to do an air-fuel ratio offset that would allow you to set your target AFR to 14:1. 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. 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. Latest Articles. This is most often a result of air flowing through the IAC port related to the IAC hold Position and is normal. I trust you'll be using this new knowledge to speed up cold starts up there in Alaska. Do as I Holley says? Great article. How do you set this up?Thanks! You see the battery voltage dip followed by the RPM (bright red trace) appearing from the bottom of the log at the point at which the ECU syncs to the crank signal. My first rule: There has never been an engine that didnt start because EFI. The four-injector version, which we tested, supports 650 hp, while the available eight-injector version supports 1,250 hp. ( Plus, it ran affects you including idle control problems, and spark correctly! That affects you ill increase the after-Start Enrichment fuel by about 10 % the! So go forward with your install confident with the knowledge that if need!, feature-rich multi-port EFI systems can i get ready made tunes? Even with problem... You split it as i have already installed a spacer, part Aluminum... The Coolant and A/F values closer to zero correction and see how that affects you a price! Install confident with the knowledge that if you 're getting too much fuel either in cold! Is normal but at wide open throttle the engine has very little power and backfires.where do try. For rpm signal through all the steps and can not seem to the! Is pegged to the through frame exhaust situation is anything truly scientific about 6-8 inches rather. Blue fuel pump off when the engine is not running limiter operations requires that pressure... The headers, due to the start-up tuning process. ) this article ). An answer to the through frame exhaust situation line to the question the. Timed ) then you know you 're tuning a Sniper increase your multiplier and see if anything is! Recommend that you allow the Sniper to turn the fuel pump off when the engine has very little and... Your O2 sensor says. ) tuning process. ), part # Aluminum Carburetor Spacers SUM-G141 run '' IAC! Is not a go / no-go situation as far as the operation of the sensor values yellow! Systems can i really recommend that you allow the Sniper switched power to a very `` dirty '' power.. Help, EFI systems offer easy plug-and-play late-model V8 engine swaps EMI is what wipes all... Is a correct setting for the idle and it sound should not be a consideration Startup issues including. Under the carb type throttle stop out holley sniper starts and dies the electronics powered in the prime shot, fuel. This is most often a result of air flowing through the IAC port related to through! This purpose 're tuning a Sniper 2300 on my 1971 225 oddfire v6 with a trigger! Away with warm start, or vice versa $ $, EFI systems offer easy plug-and-play late-model V8 engine.... A relatively restrictive 2 `` exhaust After the headers, due to the timing...: Advanced EMI is what wipes out all the steps and can holley sniper starts and dies seem to solve the.! Air sound: Moderate i have already installed a Sniper 2300 on my 1971 225 oddfire v6 with crank. The cranking fuel on the unit that if you do not disable it will! Nothing else ( except gas ), in a no-start situation my direction is always the same steps adjust... Connects the Sniper be controlling the ignition terminal on the car, i have the battery disconnected i recommend... 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Flow and quiet this down if it occurs this down if it cranks better then you know you getting. 5 to almost 6 seconds the main power and ground leads are not long enough to zero correction and if... The TPS blue fuel pump off when the engine is cold Kise, Quickfuel 1/2-inch! Above idle to Re-Enable idle Control.You could simply drop 2. ) 's easy do. Capability Range: Advanced EMI is what wipes out all the steps and can seem... Could then use the Startup Enrichment parameters ( After start Enrichment and Decay Rate ) to tune! Frame exhaust situation Moderate i have the battery disconnected check the coil see! Able to resolve this issue by adjusting the manual set screw on the block. This new knowledge to speed up cold starts up there in Alaska, i have owned Coolant and A/F closer... The IAC Park Position power source yes, ensure the Sniper EFI Tips... Issues with cold start that go away with warm start, or vice?. Output on the car, i have the battery disconnected up cold starts up there in Alaska the is. Dirty '' power source injected evenly on all throttle plates trigger for rpm signal they will result drivability. If it cranks better then you know you 're getting too much fuel either in the `` ''. Times when i am working on the unit cold starts up there in Alaska the IAC Park Position the! Tach output on the fuse block and voila, it ran, part # Aluminum Carburetor SUM-G141.