I believe because the TPS is not registering. Of the two options, I generally recommend the self-learn. Thank you. I got it home, checked it all over, everything is hooked up correctly. Sniper EFI Update: Weeks Later, Do I Still Feel It Was Worth It? I believe that you have this problem solved now with your new inline filter/regulator. You have to remove all hoses in order to debug the problem. The second thing to realize is that even after you get it just right, you need to keep an eye on the IAC number and reset the idle if it gets outside the 2-8% range when idling when warm. The learn function will offset the base fuel table until the closed-loop compensation only requires minimal changes. Some suggestions: i did have the same problem.try lengthening the lever of the throttle.meaning the length from the center of the throttle to the point where you attach your cable or your rod from the peddle. He said they have been having an issue with these lately. Holley Sniper How To Set The IAC (Idle Air Control) in 5 - YouTube Commanding the engine to automatically increase speed when switching into drive is a little scary to me though. I would not expect that an electric fan would create a noticeable load on the engine but if it did then you'd want to set the idle screw when the fan was not running. Holley Sniper EFI Self-Tuning Master Kit - Black Ceramic Finish I have replaced the IAC motor and the problem remains. Or alternator? Between the kick down and the return springs on the throttle body the pedal is so hard to push it's pretty much a jack rabbit start every time from stop, it's almost undrivable, any suggestions on what I could do?thanks for help, I've tried both Holley's tech lines for close to 2 hours with no answer! I have it set at 650 and it idles anywhere from 590 to 700. I had that problem, right out of the box it would not power up, sent it back in, had defective hand held. Seems to be working. At this time, TPS is 0%, IAC is 50 to 60%. Holley Sniper EFI Problems: Best Fixes According to Manufacturer Idle was back to normal but iac was at 0. Thanks. If you're having issues with your Holley Sniper IAC getting stuck at 20, there are a few things you can try to fix the problem. As I would slow down for a stop sign or stop light, the car would run really rough and the idle did not want to come down. https://www.gmperformancemotor.com/parts/19210007.html, http://forums.holley.com/showthread.3128#post83128, If this is your first visit, be sure to I took some pics of the sensors page this morning after the car warmed up. Sniper EFI Tuning & Tech. The broad consensus has been that the Sniper is an amazingly straight-forward install and starts and tunes as expected. However based on your reply I connected the Fuel Pressure gauge and The throttle blade adjustment is at 2-6% at hot idle, and with warm engine 185F. That is what I really respect about Holley. The Sniper even has a feature that allows it to use the idle timing to control the idle speed. Hopefully replacing the pump again will resolve both issues. Getting the throttle blades and IAC to work together will keep your fuel injected hot rod running smooth and predictable. Do you have any clue? This page was generated at 12:26 AM. However, I have never found that to be the case. But before you adjust the ECU to lean the idle out, first confirm that your fuel pressure is right. I went on the good ole interweb and found your website which was VERY helpful! 90% of problems, (INCLUDING MYSELF) could be answered/fixed by just reading the instructions. I appreciate everything you are saying. Why is this? I'd really appreciate some help. I've abbreviated it just a little bit but am appreciative of the added insight your comments provided.Off-idle performance can really be a challenge to self-learn but be assured that it can almost always be done. When you experience this, before you touch anything or shut the engine down, first look at your TPS and your IAC. Thanks again for your insights! I have an adapter on the manifold for squarebore to spreadbore and then a phenolic spacer. Even 50 RPM can make a difference in how much impact the transition to Drive has on the idling engine's ability to stay at a fixed RPM.I would not recommend it in this situation but anytime a "kick" in idle speed is desired that is easily done by setting the kick value in Tuning > Advanced > Adv. :-)Yes, learn impacts idle too, and remember the even when the basic learning is done there will continue to be some learning for changes in weather, altitude, etc.Go ahead and try a few idle settings and see how they impact the idle-speed searching. This is normally used as an A/C idle-up circuit. And your understanding of how the throttle position affects idle is exactly correct. EFI Troubleshooting EFIand and EFI Tuning Tips - In The Garage Media The Sniper will be controlling the timing so it will be based on a multitude of factors. The last pic is with the car in Drive. It has a lightweight centrifugal spring kit installed so I reach total timing around 2500 rpm. Two things to keep in mind as you do that. That is the first thing you must find. That is not the way to go. Using the handheld, navigate to Tuning > Basic > Basic Idle and ensure your target idle speed is set to the RPM you desire. There is a chance that the IAC is open but displaying 0% so start by putting your finger over the IAC opening. You might have a bad IAC, but you can also have a bad vacuum pod on the transmission. Sorta similar to a carb having the idle mixture set incorrectly (rich) or the idle speed too low. Bolt on 4150 Flange Carburetor Replacement. Fought a high idle issue until I changed your idle speed curve fix along with dropping the IAC hold to 10%. Except at idle. The problem I believe this is creating is after I start vehicle (and its still in park), the IAC drops down to my hold percentage of 10% (since throttle % is not 0) before engine is warm and therefore causing the engine to stall out. It appears that I could now use the dongle and a laptop to custom tune for idle issues if needed. Short drives is fine then it'll Unfortunately I did not buy my sniper efi from you. Thanks again Chris, your help has been invaluable.If anyone is considering going EFI, Chris is the man to chat with. The biggest issue is these problems are intermittent meaning they do not occur all the time. normal city driving, I no longer have other problems I had with the original The Sniper resets the TPS to 0% each time that you key the system on. My car will now start when its cold, but after about 30 seconds the idle drops down and begins to run like crap. Well, it turns out that with the current firmware this throws the IAC control into a bit of confusion. If you can send a data log to the vendor from who you bought your Sniper EFI System they should be willing and able to take a look and recognize RFI and then give you some ideas on solving it. If idle drops below 800 it wont come back itll chug around 300 rpm for a few seconds then die. Your comment doesn't imply any sort of problem that would make me give up on idle timing control. That, I am afraid, is going to involve a little bit of luck if you don't want to create a 250 MB data log. Seems like its too slow to grab idle when ac kicks on. The "Gauge Text" is what would be shown on a 2-1/16 gauge or the Avenger handheld display. So, clearly, the "No" answer is wrong. Hey Chris, I installed a Holley sniper on a small block 400, first start was great! Shut off the engine, ensure power to the Sniper is switched off. This may require shortening or lengthening a rod. This will go a long way to improving your fuel map without manually adjusting the acceleration enrichment. In the warm state IAC adjusted to a position of 2 to 10%. Two months fighting, cursing, not getting any help from Holley OR the forum, and a stupid little tin plate. And, hopefully, within those degrees you will find a place where you don't get the whistle. Holley Sniper high RPM - IAC problem? I think you'll be all set! A good example of why it's so important to run a good pre filter in the fuel line. Solving RF Interference Issues in Sniper Installations - EFISystemPro.com What is it supppse to be at idle and while driving under heavy acceleration? And yes, monitoring the fuel pressure is the right answer. My Sniper is 99% great! Then, the next time I cranked it, the idle went high and won't come down!" Do I need to try taping up the IAC port and setting the idle off the idle screw? I have a Holley Sniper EFI with HyperSpark ignition. Second, Holley just released over the weekend a video on how to implement a flex fuel sensor on their HP and Dominator ECU's. I keep doing that with the same result. We have never had that problem with any of the units that we have shipped. Inj. When the lambda is 1.0, the displayed AFR is 14.7;1 REGARDLESS OF THE FUEL. It is working fine when you restart the car, controlling idle perfectly at 8 steps open so it is unlikely to fail when the car warms up--or correct itself instantly when you restart it..So, if you don't have any vacuum leak, and the throttle plates are fully closed, the only thing I can guess is something is causing your ignition timing to change. I have a bone stock 350 that I installed a Sniper on and had the same whistle noise, presumably from air going past the butterflies. This car has never idled under 900 without stalling with 3 carbs and does the same thing with sniper edit. I have been reading these posts and have learned a lot. Be sure to re-enable it once you get your idle tuned. engine works beautiful, the car runs a lot, but suddenly, the engine does that. We do that but most places don't. Took it for a lap around the block and came back. I've helped folks work through a number of challenges with their Sniper EFI System installations. The latest was changing the power brake booster.Today I drove it to work and no issues at all. Hello Featured Products EFI - Fuel Injection $2.59 - $6,499.95 2179 Products View Parts Sensors Also ensure the TPS Position returns to zero at idle, & the IAC Hold Position isn't setup too high. What you are experiencing is rather common. Also when ac kicks on it will idle down and stall. The car cruises fine, and if I was to keep idle at 2000rpm the issue wont happen, its only when the car tries to ramp down to idle position.Thank you for your help, any advice would be appreciated.Thank you,Eric, Whenever we see the AFR go to "Heating" that is an indication that the ECU has been reset. (Note: in the original version of this post we had a section about checking the idle speed curve setting. Cycled the ignition off. The TPS will go red with a -15 and the AFR reads heating for a split second, then the idle kicks up to 2000RPM. Just wondered if you've ever run across a system not powering up? Engine has never stalled with Sniper system, once placed in Drive it just goes!!! All times are GMT-6. Really appreciate the amount of learning im getting off here. If the TPS is even just 2%, the IAC will go to the hold position (normally 30%) and will not change until the TPS goes back below 2%.If you create a datalog you will be better able to confirm if something is not working correctly. When you open your IAC to 30% you are naturally going to have a high idle condition. I managed to get the IAC down to around 0% - 8%is this good? A question I cannot get a 100% answer on is can you piggy back off the Sniper EFI TPS for an electronic transmission? What should I be looking at to calm this down? This is more of a bit of a reality check. $107.95. 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. Try it! Initial Baseline Idle Speed Screw Setting, http://forums.holley.com/showthread.neral-IAC-Info, http://documents.holley.com/199r11031r.pdf, https://forums.holley.com/showthread-Idle-Solution, If this is your first visit, be sure to Drive great and idles perfect at stop signs. It is probably that your RPM above the maximum point at which ramp-down can occur. I also raised idle at Park a bit with the idle screw. Cl. I did check for the lightning under the hood but all was well. The "PC Text" indicates what will be shown on the PC/Laptop data monitor or data logger. So you installed your Holley Sniper. If it is already adding fuel, it may be worth expanding this into the area where the tip-in is occuring (and where there is no learning occuring. Relatively new Sniper EFI install on a '69 Mustang 302. Do please let us know what you find out! Genuine Walbro fuel pumps are virtually bullet-proof. Thanks for the info Chris. My issue is that when Im in stop and go traffic, I can let off the clutch and the engine revs and doesnt quite want to come back to idle. I think that your Sniper system is working fine but would definitely check ouf the fuel pump. When the idle speed screw is turned all the way out there should be just enough room between the bore and the blade to catch your fingernail. The symptoms I had was a low cold start idle and going lean coming to a stop. At that point, with 90 PSI of fuel, the ECU can't turn the duty cycle down low enough to idle properly. Featured Products Sniper EFI $7.07 - $2,457.95 470 Products View Parts author Staff Writer 1711 Posts An Article About Video tech Sniper EFI Videos Sniper EFI Tech Sniper EFI sniper Installation installing and cruising down the highway 70 mph I just wonder if all I have to do If you don't have a working coolant temperature sensor then it will never bring the idle speed down. TPS 0. :-). This minimizes installation time and packages really well on a diverse group of engine applications. other things that might cause the idle to faulter, but this is a good start. is train the system or there is actually something wrong.I do love the system at I started with right after I first adjusted for 2% IAC and took pics about every 30 seconds over about 2 minutes. If it is not a problem with the Sniper EFI System itself then it could be an issue with some sort of harmonic involving the fuel pump. 34K views 1 year ago Holley Sniper How to Set The IAC Idle air Control in 5 minutes or less. Stupid question, but where do I see if it's entering Learn mode? When you key on, you will hear three distinct sounds: The ECU initializing the IAC, the fuel pump priming, and the injectors firing their prime shot. As you see above, the Sniper is going to dump in a maximum amount of fuel at zero TPS, begins to remove acceleration enrichment at 60 percent TPS, and then removes all acceleration enrichment correction at 100% TPS. I would suggest at that point you need to contact whoever is providing your tech support and find out why the default values are not working for you. :-). To start viewing messages, select the forum that you want to visit from the selection below. In fact, it is those users who seem to end up most impressed with the system. IAC is good 0-5% most of the time. He is able to get it to start by quickly depressing the accelerator to at least 60% and releasing. I asked him a million questions and waited a long time to save up before purchasing the system and I have asked a lot of questions throughout the installation process. A problem since day 1 - YouTube Leave a comment if you've had this issue and how you resolved. I have quadruple checked my wiring and am certain it's correct. If there's any run time on your current setup the Sniper may have some bad learn data due to what appears to be timing issues. I will a, Scott has been very helpful and informative on guiding me through the purchasing and installation of my terminator X max system. Ok, we have enough Sniper systems out there that I thought it would be a good idea to create a posting on challenges that might arise during installation. If it does then you can put on a heavier spring so the advance doesn't come in as fast, or use a lighter weight. You might even want to add our 4-foot extension harness that will allow you to connect/disconnect the display or CAN-to-USB adapter from inside the car (rather than trying to do that leaning over the engine and under the breather. The on board fuel pressure regulator in the Sniper throttle body has a small filter clipped over one end . that my Air/Fuel ration was 15:1 and I believe the target is 13.5:1. Observing the temperature on the 3.5-inch handheld (only), wait for the temperature to achieve 160 degrees F. Once above 160 degrees, turn the idle speed screw so that the idle is about 50 RPM below your target idle speed set in step 1, above. Capability Range: Advanced Member List; Calendar; Forum; Holley EFI; Sniper EFI; If this is your first visit, be sure to check out the FAQ by clicking the link above. Hello Chris. Also, I was seriously rich at idleso rich it hurt your eyes. I've not heard of any others with this exact issue so I don't think it is a common problem. This happens no matter how much I adjust the idle screw. Until the engine starts, the throttle only has one purpose: To detect you pressing it to 60%, at which point it shuts off the fuel injectors. Physially manipulating the linkage by hand will generally reveal if you have a sticking linkage that is preventing the TPS from returning from zero. Also its extremely rich at idle. I have verified that there are no vacuum leaks, not to mention the car runs to good to have a vacuum leak bad enough to make this noise. I installed a Holley Sniper on my Ford Maverick 302 V8. It'll start & run till it's warm, then when I try setting the IAC every time, I try getting it between the 2 & 8% it quits. Hopefully replacing the pump again will resolve both issuesWhoa. Turned it off and on again. Robust, feature-rich multi-port EFI systems offer easy plug-and-play late-model V8 engine swaps. Next, reach down into the secondaries and push the butterflies closed. (Plus they it just looks way cool in your engine compartment!) You will find a startup IAC percentage, an amount of time it holds at that percentage, and an amount of time it takes to idle down to the normal idle speed.By default, that number is 50% at normal operating temperature. Any idea's? Drives just fine but won't stay running unless I keep my foot on the gas. Plus, you can email that file to me and I can be of more help. If I put the vehicle in gear the idle gets higher with temp. Duty Cycle% = 3 Once you confirm the operation of your IAC then it's time to read my article on Solving RFI Problems. That's a nice change of pace--a low idle issue! I certainly appreciate your frustration (as well as your wife's!) I am at the point where I almost insist that every Sniper EFI System owner purchase one of these. And thanks again for taking your time to answer these questions. idle at 1100 on the "stock" file it's better with street strip.The IAC counts will be at zero. It turns out that some of the Snipers are shipping with the minus 40-degree setting drastically lower, as shown in the following image. Only show this user . Ensure there isn't a vacuum leak causing the IAC Position to drop to 0%. But, whether your vendor provides you with tech support or sends you to Holley, I'd start by getting them a data log and asking for some insight. If the engine idles at 750 RPM with the throttle plates all the way closed and the IAC at zero then there is some sort of an issue. At 0% it shouldn't be sucking any air through that port, correct? Idle quality is great, RPM is good, sometimes IAC is jumping around from 35 to 60. It could be that the air flow across the secondaries as they are opening is creating that whistle but that isn't commonly the case.Did you check for leaks around the gasket of the air cleaner? The engine has 14: 1 compression ratio, we can not use gasoline. I followed the instructions and set the IAC to 2-9% when warm with idle at 850 RPM. Chris thank you for the info. If not then I think you are going to find that this will solve much of your problem. The next time it happens is the perfect opportunity to find the problem. I did change the -40 thing also. May God's grace bless you in the Lord Jesus Christ. The IAC going to 30 is normal. Car was running great initially. So check that timing and I think that you're going to find you need a good bit of advance. First, recognize that the IAC and the TPS are not inter-related in any way. mean that the IAC is causing it. The weather in Ct has finally improved and I have put about 60 miles on the car with the Sniper system. Across the board, all of our customers say how impressed they were that it started and ran right out of the box just by following the simple installation instructions. I have certainly seen this before on other fuel injected vehicles when hot. In the time it takes to add your email address you can be at the top of the heap for getting the latest information from our authority. So something is triggering the ECU to be in Open Loop. I have checked the pink wire and it is at .001 volts when key is off. This page was generated at 12:25 AM. After a complete cool down it will do the same thing. Use the idle speed screw to set the idle at a comfortable warm-up speed. Sniper EFI Idle Tuning - Holley Motor Life Should the iac% fluctuate? When you first posted this I had no idea how to respond. The fix? With select intake manifolds, the distributor housing and IAC valve on the back of the Sniper EFI throttle body are fighting for the same . Anyway I have a 327 sbc in a 1987 Monte SS with a T5 5 speed and 3:73 posi rear. Is there any chance that your timing has changed since you installed your Sniper? Thanks for any help. It's called tuning. :-). That is not a huge problem but it just means the IAC has no ability to lower the idle beyond what it is running at that point. But they are 100% committed to your satisfaction. When I cover it with my hands, it gets quieter. I have tried your 10-step idle adjust and ive adjusted the idle curve. But I am having troubles.When stepping on the accelerator slightly with idling, it will be 2000 RPM all the time. % = 49 Jump on board now! That A couple of those and you should feel it getting better. If you have an installation or start-up issue that is nagging you then please use the comments section to reply and we will gladly provide more information that we hope will be useful to you. So what--you're never going to drive in minus 40 degrees, right? I'm new to the efi thing and any help would be seriously appreciated. Doesn't want to start, runs like crap. This software is going to allow you to open both the configuration file and the datalogs that you create, overlay them and you can get a much better idea of what is happening. You will need to change the -40 degree idle speed setting again but I recommend not touching anything else. It is good to at least know that the Sniper fuel pressure regulator can have high pressure failure issues (contrary to what I posted to Scott back on April 13th!) You can adjust this number up or down but there is really no need to change it unless the car is stalling.The sucking sound is just what happens when the Sniper EFI System is paired with certain intake manifolds. )Take a look at your AFR during the starting process. You should get a light spray evenly distributed in all four barrels. Idles ok, runs great cruising, but from a stand still or downshifting and making a turn, when I get back into it, it wants to fall on its face.