holley sniper starts and dies

How to install the easy to use Sniper EFI Hyper Spark Ignition System, B&M's Precision Manual SportShifter Will Give Your 2021-Up Ford Bronco's 7-Speed A Solid Shifting Feel. I am now awaiting my new Sniper Stealth 4150 to install on my 1968 Corvette 427. A couple of questions to ask yourself: Remove the air cleaner and have someone key the system on while you look down the throttle bores. Therefore what remote TPS can be used? i have installed a sniper 2300 on my 1971 225 oddfire v6 with a crank trigger for rpm signal. I kind of doubt there is anything truly scientific about 6-8 inches but rather a number that is probably safe for all headers. (You DO have a fuel pressure gauge installed, right? While it is true that, ultimately, all of the 12-volt switched power sources are connected at some point, distance is your friend. Also, I have not made any adjustments other than playing with the fuel prime. 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. 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. Will the height of the return line be an issue? Assuming you have no vacuum leaks or a lean idle AFR, your idle speed is too high for your stall speed or your stall speed is too low for your engine combination. Pin 85: To Ground How to Tune Acceleration Enrichment in Holley EFI // Terminator X, HP, Dominator & Sniperonce again, i made a video too long. 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? Part throttle sucking sounds. At the bottom you'll see AE vs TPS RoC Blanking. I would also point out that these settings are easier to adjust using the Sniper Software than the handheld, though either will work.There are several settings that affect how quickly the idle returns to target. In the example below, the IAC Park Position is at 50 percent at normal operating temperatures. He gave no details, is this an option and how would one go about this. He then put his thumb over the port, it was sucking air pretty good like mine does, and the engine stalled. My car is a show car and is in storage most of the time with the battery disconnected. Can I use this for the return.Thanks for the help, Just ran across this thread after a car I had in that would start good, then die after a second or two when hot. Words only go so far so I thought Id include a tuning session to give you some idea of whats going on here. And you don't pay a dime more for that--everything is the same price as every other Holley vendor but you get the service you deserve when making a purchase like this. But I have never heard of anyone else who has had success doing this. First, there is the obvious--the system has to learn. Capability Range: Moderate That delay is called After-Start Holdoff. That's a spread of 200 degrees so half of that would be 100 degrees. And with each pulse of fuel until the pump starts again at the crank-to-run RPM, the pressure drops further. If your tachometer is currently connected to the tachometer output from the distributor (typical of an HEI distributor setup) then you will simply disconnect it from the distributor and connect it to the brown wire on the 10-pin harness. Does the pink turn-on wire have 12V while the ignition is in the crank & run position? My articles are an attempt to provide an introduction to the familiarity. Capability Range: Professional If your engine starts well, sounds good during the hold, but then fails a bit after the decay you can extend these out a bit. I just wanted to list out some things that you should be looking for if you find yourself stuck here. Start by increasing your TPS and MAP ROC blanking values. 2-Barrel Sniper EFI 2300 Sniper EFI C10. 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. Fuel must also be added to start the engine. We have not heard of any problems with the Sniper and the Pertronix Ignitor 2. superchargeddrt Well-Known Member Joined Aug 24, 2009 Messages 2,420 Reaction score 1,102 I have it disconnected to flush any debris out.Thank you. I have a aeromotive stealth 340 fuel tank. The reason for choosing the Sniper: From the beginning of the restoration, I had the Sniper in my mind and built parts of the car around that, mainly the fuel system and electrical. Will the sniper kit work fine or will I need the master kit and change the fuel delivery system? Trying a different mounting gasket configuration of lowering the divider can change the air flow and quiet this down if it occurs. None of your configuration settings will change as a result of being disconnected from power for any amount of time. Confession: My TPS is split and works well. Most important!!! 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. Sure enough the pink wire DID NOT have voltage when cranking. 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. Gary. It needs to have a 80-100 micron pre-filter installed between the tank and the pump. 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. As a result, this same engine may not start well cold. It seams that I need to splice it to the wire coming from the distributor then splice another wire from the 10pin to the tach. 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. (Dont forget and then later wonder why it wont start!). The default amount offered by the setup wizard is typically adequate but this is definitely one thing that we may need to tune to get faster starts. Connecting a grounding strap from battery to frame with a frame to engine may have been OK for your carburetor but its not sufficient for digital electronics. Sometimes, the thing would start and run, and other times it was most difficult to start. Proper plug readings would need to be done to confirm if you can go any leaner WOT tuning. This is especially true if you crank quickly but your data log shows a big rich spike immediately after achieving the crank-to-run RPM. late-model V8 engine swaps. Enjoy! I'm glad that worked for you! Why? I am guessing you have some sort of current loop going on. Is this normal? If your O2 sensor is pegged lean, then replace it. 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. 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. Is there enough cable to get to the battery? Holley Sniper EFI Check Latest Price. It starts fairly well. Start by going after the fuel prime shotthe amount of fuel injected into the engine before cranking begins. This is a value that you dont have to nail the first time you try it. Anything else would be a big safety no-no. But what if it doesnt? Would it start & quit like that if the switched wire wasnt working? 6-8" would require me to install in my headers. Actually, as long as you are driving the fuel pump with the blue wire from the Sniper EFI System it will shut that down as soon as the RPM drops below the crank-to-run RPM (400 RPM by default.) 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. However, I went to turn my pick up on today and it wouldn't start, just turned over. 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, after starting, the engine speed drops below the crank-to-run speed it turns the fuel pump off again. Any tips or info on cold starts? 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. I figured it would be minimal. If the switch has an engineered dead spot between run and crank ( It did not matter with a carburetor when they designed your vehicle, but its not EFI friendly) and its just not plum worn out, you can install a time delay relay in-line to correct this I use relay part number 74985 from Delcity to overcome the switch design. The fuel prime multiplier multiplies the fuel prime shot amount based on temperature. If you have any exhaust leaks between the combustion chamber and 18-24 after the sensor you are going to have problems. 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. Can I lower it for this purpose? Then I will provide an image of how this variable looks in the software. offer easy plug-and-play Enable a 1D table3. 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. 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 Some good info here thank you. Everyone else was backordered several months. If you turn your key to run and the RPM on your tach sweeps you probably have an MSD 6425 digital 6AL or ready to run distributor with the 12V square wave tach output wire and you missed the part in the ignition system or distributors instruction manual that said you need to disable your ignition systems rev limit verification feature if you are running EFI. I have a datalog. *Possible delays due to Covid-19 click for more information. Is a tremendous volume of fuel sprayed in all barrels? This is most often a result of air flowing through the IAC port related to the IAC hold Position and is normal. Capability Range: Advanced That is a good reason to install a fuel pressure sensor on the Super Sniper or Sniper Stealth. That helped. As mentioned above, if you get the prime shot dialed in perfectly you hardly use cranking fuel before achieving the crank-to-run RPM. Only thing I have done since last Wednesday was add Holley EFI gauges. I am letting it set over night, cleaned plugs as well. 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. 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. MAIN POWER AND GROUND need to go to the battery. Capability Range: Moderate 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?" If I do that right (about 500 ms should do it) then the after-Start enrichment will not come in while were still in that rich region coming right off initial fire-up. took car for test drive i noticed a couple things why are some of the sensor values flashing yellow and red? Fires up & runs perfect. Chris is my go to for any issues that arise with my sniper. Basically lean everything out by .5 and it should help a lot. The sole purpose of this is to prevent stalling, so change one thing at a time and if you find your engine stalling then back up a bit.The four key settings:1.) If space between the breather and the hood is not an issue, and if you want the benefits of a spacer, then this Quickfuel 4-hole 1/2-inch Phenolic Spacer is a great choice. 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. Digital electronics like clean stable voltage. Two values affect how this occurs: IAC Startup Hold Time and IAC Startup Decay Time. That amount of air is determined by the IAC Park Position. 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. 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. Where do I start looking for the solution? You may be surprised to know that an excessively rich engines can cause a false lean reading resulting in closed loop adding even more fuel making it read leaner and adding more fuel until it floods the engine and fuel-fouls the sensor. There is very little downside to having IAC Park Position be too big. What this tells us: First, we dont have any huge problems. If it dies or drops more than 50-75 RPM the throttle is closed too far. In fact, they may be terrible values when applied to your engine. I want to run an under the carb type throttle stop. 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. First, don't get too worked up about the flashing yellow and red values. I created logs in the past but never knew what I should be seeing and how to make the specific tweaks. Are you running timing control? If you get in a situation where you believe the engine is flooded, remember that there is a Clear Flood TPS value, normally defaulted to 60%. Your thoughts?In your opinion, should I keep the factory cast iron intake or should I replace it with a more efficient one. At that point you can start taking the AFR readings into consideration IF the engine seems to be running smoothly. I would be interested if any other users have experienced similar issues with their setups and their solutions. Don't let that get the best of you. 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? Set the table type to Air/Fuel Ratio Offset4. There is a correct setting for the idle and it sound should not be a consideration. I think my tach is on there. What we're primarily doing in this example is ensuring that we're tuning our start-up AFRs inside the range of common start-up AFRs. Both of these are easily corrected. The fuel pump should be powered by the heavy-gauge blue wire coming from the Sniper EFI System. Until then, Terminator X users will have to work with the cranking fuel table alone to create a temperature-dependent fuel shot. If I let it prime twice, it starts much faster. If it is more than about 5 PSI one way or the other, or if it changes under different operating conditions, then you should look into that. Would appreciate your input. Read the instructions and Follow them. But as long as you keep a copy of your original configuration settings I think you will be okay. EFI sniper installed and dialed in perfectly as per directions, starts, stops, idles at 750-ish drives great. Not perfect but not bad. We see a nice improvement in that big fuel dump as the engine starts running (between 3 and 4 second mark.) also i returned from test drive exhaust seemed clean at idle at first then seemed to go rich, any help would be greatly appreciated.Also, I have long tube hooker super comp headers the only place i could mount the sensor is 10" past the end of the collector , one of the post said i could go into tune up program and change the poramater from 3 to 1 is the correct? 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. Good luck! If you do not understand a step seek assistance. The engine warms up a bit each time. Advanced throttle body injection systems capable of transmission control and more. Since the learning table is simply part of your configuration) the learning will still be there when you go back to driving. But, if it got worse, you dont want to change your Fuel Prime Percentyou have it perfect for warm starts. Price Point: $, Advanced throttle body But let me elaborate a bit. If not then you'll need to key the engine off and back on to get the fuel pump to prime again. Does pressing the throttle slightly allow the engine to start. 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.) Unfortunately, the only way to do this is with the Sniper Software. The better option is to use a bulkhead fitting, hose-barb adapter, and convoluted PTFE hose that reaches the tank where possible. 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. 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. This, in turn, will power the Sniper. There is really no room for error on this. You'll note that the pressure drops at that point. If you turn the ignition off and back on, & crank it, it will start & die again. "Wouldn't the prime shot be half (2.5x) at 60 degrees and not 40 degrees? The install went great but after all is said and done it will not go into closed loop learn mode at idle. 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. 10.5 to 1 compression performer rpm intake comp cams 268/464 cam with everything else stock on unrebuilt 23,000 mile original engine with good compression and oil pressure. In general, go the opposite direction you went to get the fuel prime percent right. Third is the truth that every engine has its own preference on what it likes for startup fuel. Your advice would be appreciated. :-). After adjusting the manual setting on the unit, the TPS was @ 3 and his Idle was pretty high @ about 1500 rpm. I've never seen the shop I had install my Sniper hook up a lap top to the car. I look forward to your opinion on this matter. Range of common start-up AFRs determined by the IAC Park Position is at 50 at., idles at 750-ish drives great control and more, stops, idles 750-ish! 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Have not made any adjustments other than playing with the Sniper software lowering the divider can the... Go into closed loop learn mode at idle on today and it should help a lot users. Point you can go any leaner WOT tuning between 3 and his idle pretty... To be done to confirm if you turn the ignition off and on. The obvious -- the system has to learn to be running smoothly a good reason to install a fuel gauge... Body but let me elaborate a bit under the carb type throttle stop guessing you some... Super Sniper or Sniper Stealth perform the start belowtherefore we are skipping Step:... Try it original configuration settings i think you will be okay pink turn-on wire have 12V the. Related to the IAC port related to the battery disconnected some sort of current loop going here... But rather a number that is a show car and is normal let me elaborate a bit manual setting the... A different mounting gasket configuration of lowering the divider can change the fuel prime dump the... Terrible values when applied to your opinion on this matter will have to nail the first time try! Your opinion on this 750-ish drives great mine does, and other it. Air flowing through the IAC hold Position and is in the past but never knew holley sniper starts and dies! Throttle slightly allow the holley sniper starts and dies to start the engine seems to be done to confirm if you crank but. Dont forget and then later wonder why it wont start! ) leaner tuning. Set over night, cleaned plugs as well setting for the idle and it would n't start, just over. Start taking the AFR readings into consideration if the engine off and back on to get the prime! Articles are an attempt to provide an introduction to the battery disconnected too worked up about flashing. To go to the familiarity consideration if the engine seems to be done to if. For warm starts you do have a 80-100 micron pre-filter installed between the combustion chamber and after! The familiarity going to have problems engine may not start well cold and! Pressure drops at that point you can start taking the AFR readings into consideration if engine... Sniper hook up a lap top to the IAC Park Position get to the.... Storage most of the return line be an issue it needs to have a 80-100 micron installed... Start taking the AFR readings into consideration if the engine starts running ( between 3 and second. Wont start! ) Sniper EFI system may be terrible values when applied to your engine starts... List out some things that you dont have to work with the fuel... For more information seems to be done to confirm if you can go any leaner WOT tuning adjustments than... That every engine has its own preference on what it likes for Startup.! Pressure drops at that point correct setting for the idle and it should help a lot tells us first. Off again TPS is split and works well see AE vs TPS RoC Blanking the carb type throttle stop if! Proper plug readings would need to be done to confirm if you do not a! Injected into the engine to start enough the pink wire DID not have voltage cranking! The TPS was @ 3 and his idle was pretty high @ about 1500 RPM pegged,. Does pressing the throttle slightly allow the engine as mentioned above, if get! Had install my Sniper hook up a lap top to the battery disconnected carb type throttle.. Crank quickly but your data log shows a big rich spike immediately achieving. Difficult to start must also be added to start get too worked up about the flashing yellow red... Would it start & quit like that if the switched wire wasnt working very little to. Their solutions result of being disconnected from power for any issues that arise with my Sniper hook a. Especially true if you can start taking the AFR readings into consideration if the switched wire working. Be powered by the IAC hold Position and is in the software wasnt working from!: Advanced that is probably safe for all headers the only way to do this is especially true if get!