It works instantly for him.If that fixes your problem then you have a starting place. I recommend you have a look:https://www.efisystempro.com/efi-pro-hangout/holley-sniper-efi-instruction/solving-sniper-rfi-problems, I recently purchased your fixed linkage to open primaries first and the throttle linkage extender to also get a smoother pedal. close to idle with the IAC between 2% & 12%. I have a Holley Sniper for almost 11 month now and it was running fine with no problems until now. any ideas? Holley Sniper EFI Problems: Best Fixes According to Manufacturer But after sitting static idling for a little bit, the IAC goes to 100% & stays there. Once you confirm the operation of your IAC then it's time to read my article on Solving RFI Problems. As inconvenient as it might seem, I'd recommend keeping a timing light handy and checking your timing during the high idle condition and then again after restarting. I've helped folks work through a number of challenges with their Sniper EFI System installations. I've been trying to correct that 1% small issue/annoyance. After only running for about 15 minutes or so the system starts to fail stalling the motor. Lubricate the linkage so there isn't as much native resistance. I never had a problem with this. is train the system or there is actually something wrong.I do love the system at Wish I had bought my sniper from you, but unfortunately didnt. The first 250-300 miles were amazing as the Sniper EFI worked flawlessly. So something is triggering the ECU to be in Open Loop. The small rubber plug had a leak. Idle > IAC Kick. Let Hello, Chris, thanks for the help.I have not installed the software yet, and I'm having trouble with two cars. I will a, Scott has been very helpful and informative on guiding me through the purchasing and installation of my terminator X max system. That is what I really respect about Holley. Yes it is controlling the timing and I had issues at first and it controlled the idle just fine. I have checked the pink wire and it is at .001 volts when key is off. Yes, let me know how that setup process works. 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. Hello. Check fuel pressure too (. And so glad you guys are enjoying the Sniper EFI system. Pw. If you go too low then it may stumble or even stall when coming off of throttle. If not then you have some other issue that is behind this increased idle. There are a few tell-tale signs that can help you diagnose the problem. Robust, feature-rich multi-port EFI systems offer easy plug-and-play late-model V8 engine swaps. Sniper EFI Problems - Holley Performance Products Forums There is no sense proceeding until your TPS is at zero at key-on. I installed the Holley gauge you suggested in another thread at the fuel input to the TBI, and the fuel pressure is constant around 64 according to the gauge. Sniper setting is Stock camshaft. One of the best Ive seen so far. 63 bomb This increased idle speed is triggered by grounding the orange wire in the 10-pin I/O harness. 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. 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. Only in the unlikely event that your engine simply won't run well enough to drive and self-learn should you consider tweaking anything inside of the first several hundred miles. Sniper is still learning so it will continue to improve.Second, you may have heard the phrase, "correlation is not causation." We offer some tips to help with that. Tried that and it didn't work? I am new to the EFI scene but want to learn. At some point you come upon problems that evade the easy answers and this is a good example. installing and cruising down the highway 70 mph I just wonder if all I have to do In the wizard I set my Idle to 500RPM but it never got slower than 800RPM, if I run the wizard again and lower to 400 RPM then it never gets lower than 700RPM.After reading about the Idle Speed curver I checked its settings and found that the curve was 300rpm faster at every point over the temp range no matter what temp I had, I adjusted the curve to match what I put in on the wizard and now the RPM is correct, I'd say you have a bug in the wizard.Idle Speed > Idle Speed Curve: Here is where the lack of coolant temperature is going to affect you. Going in the direction you did (higher) is going to reduce the acceleration fueling that the engine sees. Now that you've got your IAC set I'm going to recommend that you run your setup wizard again, which will reset the ECU to the default settings. We're never going to fill up your email box with nonsense. After it starts it idles around my 960rpm setting + or - 100rpm. It appears that I could now use the dongle and a laptop to custom tune for idle issues if needed. Okay, try my method. Resistance results in heat and heat results in more resistance. Second--even in the HP and Dominator systems where a fuel pressure sensor can be dalogged and displayed, the fuel pressure is not fed back into the algorithm. I appreciate everything you are saying. The noise is definitely coming OUT of the throttle body. I installed a Holley Sniper on my Ford Maverick 302 V8. Though it started and ran good, it was dumping fuel and would not lean out to AFR set points. Not good.There isn't set solution here that works for all engines. I keep wondering how it was running so good with It wont fire up. Which means you either need to increase that number or increase the ramp decay time. port that goes right on the inlet of your Sniper and makes installation a breeze.If your fuel pressure is solid at about 60 PSI then you should start looking at I have quadruple checked my wiring and am certain it's correct. EFI parts, including the throttle body, and the problem persists.Please give me a hand. Do I need to try taping up the IAC port and setting the idle off the idle screw? I am having an idle issue (other than that is absolutely perfect). My Sniper started having a ticking noise-- I have 90 miles on my Sniper, but this started the last 10 miles or so: it still drives fine, but it worries me so i've stopped driving it for now. Your task will be to find that. The Sniper Quick-Start Manual provides the following instructions for setting the idle. Holley have given a new unit. I did all of this before seeing the link you sent. And since they really had an insanely-tight monetary and real estate budget in the Sniper EFI System, it is unlikely that the added something that wasn't absolutely necessary--and then forgot to use it..And you are spot on about the little Earl's gauge with optional -6 AN port. Yes, it will talk to you--but not with words. I've been messing around for a bit trying to eliminate any possible vacuum leaks. Get that thing installed and you're going to know a whole lot more about what's going on. Simply go to those cells, tweak them up or down as required, and the ECU should now be able to learn its way around the bog. Going lower with the blanking might pay dividends, but there is so little room below 7/8 that you will quickly be in a range where every tiny variation in the TPS or MAP is throwing extra fuel into the engine. So this is my issue ( I did just email Holly). As I said I didn't buy from you so you don't owe me anything. Once you have done this the challenge is to create a datalog that includes the ":snap" you describe. Holley Sniper IAC Surging???? Hello Chris. The manifold pressure increases with the throttle opening but the RPMs are still low. Good luck! I set it exactly like the instructions said and my iac is not only all over the place but when I finally did get it to the 2-10 range it's highlighted in red. The IAC is hanging open and not really at 0. Edit I just ordered a Holley return / regulator and cap for the sniper ouletOh, this is not an OEM Master Kit, but the fuel pump should be the same EFI Pro shipped this kit. By the way your site and your accessory products are nice. Solving RF Interference Issues in Sniper Installations - EFISystemPro.com Initial thought is timing but Im running a cd box and the ecu is not controlling and I did not physically change it during the install. By the time I was near home, the idle in Park was 1050, IAC 0. Give it a watch: https://youtu.be/7SO7-tZn6iw. That is not something I'd ignore. It will learn the fueling eventually either way, it's just that one might get you there a little faster.If the idle is fine at start-up but then increases after you depress the throttle then you might need to lower your IAC Hold Position a bit. A couple of possibilities that come to mind in order of likelihood: Im having an issue with what I think is the Iac. I keep doing that with the same result. Since a key cycle resets it to 0 and out to 30 or wherever When I removed the tape and started it again, it was idling at 1400-1500 RPM and sucking a bunch of air through the IAC, even though it showed 0% on the sensors screen (pic attached). 90% of problems, (INCLUDING MYSELF) could be answered/fixed by just reading the instructions. Hey Chris, I installed a Holley sniper on a small block 400, first start was great! Purists will sniff that these are not accurate to the tenth of a PSI. I have a feeling it's something simple but I thought I'd ask you first before I inadvertently change something that affects other areas. Remember that as an EFI System Pro customer you have access to me at any time via my cell phone. 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. Yes, it will talk to you--but not with words. You can manually set it 57 after you run the Wizard if required. Shutoff engine wait 30 seconds, turn key wait for display to come up, start engine. Holley Motor Life I have adjusted many settings and eventually mess it up and go back to the original map. mean that the IAC is causing it. Running a bbc with coil - my timing is perfect. Reducing that a bit will help. If you feel you have no other choice but to run a Sniper and stand-alone controller then you can give this a try. Capability Range: Professional When I drive with warm engine the IAC is at 30% when pushing gas, but shouldn't it be at 0%? Car was running great initially. Also when ac kicks on it will idle down and stall. It may take a few tries. The noise changes sound with the throttle position. Hang in there--you can do it. That could be a problem with the TPS or it could be some sort of throttle linkage issue. One of the great features of Holley's Sniper is the ability to set your air/fuel ratio (AFR) where you want it. have the system learn the higher speeds? Holley - 543-105 EFI Idle Air Control Motor , Black - amazon.com Hi Chris , greetings from Down Under (AUS) Just a note on the hi fuel pressure issue . Or, at least, it should. Laptop Access Cycling the power to the Sniper EFI would cure the problem, but not prevent it from coming back. If I were there in person I would test the function of the IAC (see this article.) This may require shortening or lengthening a rod. The engine might run hot but if the timing is right it should keep that heat in the engine--which is where the damage turns up. Changing the rpm curve and target rpm has no effect. Incorrect connections will result in excessive resistance. The tps has slotted holes, can you adjust it to get to zero? I have an entire article on choosing between Sniper and Terminator X throttle body solutions and while Sniper is still a sound choice for some applications, Terminator X (with transmission control) is hands-down the way to go for those who need that. And your understanding of how the throttle position affects idle is exactly correct. I'm new to EFI and have no idea what to try next. You might have a bad IAC, but you can also have a bad vacuum pod on the transmission. Technically it is a warranty-voiding maneuver so proceed at your own risk. The Street/Strip and race cam setups tend to be too rich initially. I followed the instructions and set the IAC to 2-9% when warm with idle at 850 RPM. However, I have never found that to be the case. Earl's Mechanical Fuel Pressure GaugeI could use that for a quick troubleshooting for 1/3rd the cost of the Holley one. Then, when you experience the high idle, note if the IAC number has increased. Bolt-on carburetor style EFI for your classic car or truck. I have driven it a few times maybe 100 miles or so. Next, reach down into the secondaries and push the butterflies closed. Bolt on 4150 Flange Carburetor Replacement. Thanks again for your insights! Commanding the engine to automatically increase speed when switching into drive is a little scary to me though. In that case, and if you have an EGR valve, I might be suspicious of something going on there. The fuel pump is mounted under rocker panel as low as possible and far away from any heat. I am having an issue with the IAC on the Sniper. I would only play with this if you are finding that the other adjustments I suggested aren't working. If your TPS has snuck up to 2% then your IAC will be at the hold position, which by default is 30%. Now that you've installed at least four Snipers it is going to be imperative that you learn to create and read datalogs. Others might require 60 RPM. I installed another return spring for the rear plates problem solved instantly. Now, 1% on the TPS isn't a problem, but when it goes to 2% (which is inevitable if you have RFI moving it to 1%) then the IAC is going to go to it's hold position (30% by default) and the engine is going to rev up. Cl. That way you can get into that part of the table that needs tuning, and you can watch your learn numbers grow. Cycled the ignition off. THANK YOU for the "First--Check Your Idle Speed Curve Setting!" Coming home from work today it was much warmer and took a little longer due to traffic. Fought a high idle issue until I changed your idle speed curve fix along with dropping the IAC hold to 10%. Then it started behaving oddly. I've not heard of any others with this exact issue so I don't think it is a common problem. datsun sniper efi Holley RetroBright This 1974 Datsun 620 Bulletside Cruises With The Help Of Sniper EFI Bradley Iger 01/13/2023 features Latest News sweepstakes 2023 Hemi Engine Sweepstakes Gen III Hemi Enter To Win Holley's 2023 Hemi Engine Sweepstakes For Your Chance To Win A 600+ Horsepower 392 Stroker! I know its not flooded because I can pour a little gas in the throttle body and play with the accelerator and it will start and run fine. Once it commands that high idle I haven't found anything to return it to normal, other than shutting it down and restarting. It sounds a little different from mine, since it commands a 1300 or so increase intermittently. The learn percentage should gradually decrease to virtually nothing as the map plus learn table begin to get more and more accurate to your specific setup. Overview. It really takes a lot of throttle tip-ins before you get anywhere near "learned" in this part of the fuel map.Based on your description, it sounds like you have a lean stumble. It's going to be really difficult to nail down the problem with the several simultaneous changes that you've made. Is there any chance that your timing has changed since you installed your Sniper? Jump on board now! The Tech Tips and discussions are also great! When you first posted this I had no idea how to respond. Hopefully replacing the pump again will resolve both issuesWhoa. May God's grace bless you in the Lord Jesus Christ. I had HIGH Idle issue and fixing this curve FIXED the ISSUE --- THANK YOUCan you explain what "Current Learn % means, after finally fixing the idle problem this % jump from -1 to -30% in about 5 minutes at idle with CTS @ about 170.Also when starting the car at hot the engine goes to about 2300+ RPM for a few seconds then crashes down to my Hot idle speed of 950 -- bounces a little and then smooths out. The biggest issue is these problems are intermittent meaning they do not occur all the time. 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. When I covered the IAC with my finger, the RPM dropped so low it stalled. (It should be at or near 60 PSI at idle. When you open your IAC to 30% you are naturally going to have a high idle condition. I have certainly seen this before on other fuel injected vehicles when hot. I think that a great number of the challenges that Sniper EFI System Owners face are brought on themselves by getting into the control settings before the system has really had a chance to learn. I would gladly engage with you to solve this but ultimately you are going to need to go through whomever you purchased the system if a warranty return is in order. But get that fuel system fixed before going any further. P.S. >I'm using russell hi pressure gas line to feed the gas up to the sniper and using the stock steel gas line that use to be the feed line for the carb to return the gas to the tank. 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. It is simply for the benefit of the user. If not then I think you are going to find that this will solve much of your problem. Unfortunately I did not buy my sniper efi from you. Kind of cuts into forum time. Hi. me know how it works for you. Plus, you can email that file to me and I can be of more help. Sniper EFI Initial Startup and Troubleshooting Staff Writer 01/20/2020 Well you were right air was entering from another source. Took it for a lap around the block and came back. One of them might be faulty. 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. The RPM would increase for no reason. You could install the Holley Dual-Sync Distributor and let the Sniper control your timing. You could go either way.. That will at least tell you something. Holley documentation and videos didn't work and the $300 I paid for "expert" tuning didn't work either. I had that problem, right out of the box it would not power up, sent it back in, had defective hand held. You may have to register before you can post: click the register link above to proceed. holley efi. We will definitely be sticking with Holley from here on out for future retro-fits. I have driven a stand-alone transmission controller for the 4L60E in my (then) Sniper-equipped '95 GMC pickup using the Sniper TPS with complete success. Copyright 2022 Holley Performance Products, Inc. All right reserved. I very pleased with the performance, it is a huge improvement from the 800CFM carb I had on this motor. But they are 100% committed to your satisfaction. Capability Range: Moderate 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. i'm having is I can't seem to get the truck to run faster than 45 mph at speeds But he kept having problems so eventually he did a complete check and then he found the problem. As I have it set right now, my idle at park is in the high 700s and my desired idle in gear is set at about 700 cold (80 degrees) and gradually lowers to 590 once engine temp reaches 160 degrees. Thank you chris for for getting back to me on this matter.I'm using russell hi pressure gas line to feed the gas up to the sniper and using the stock steel gas line that use to be the feed line for the carb to return the gas to the tank. Generally, one of two things: a stuck throttle or noise on the TPS signal. If Reply Quote. This value is itself enough to raise the idle a bit. After pumping the pedal a few times at different times it dropped to zero and started to work. But now that Terminator X is available, I highly recommend going that route. I thought 12.0 was leaner at idle, but I figured out I was wrong.lol. I'd suggest that you assume everything the previous owner did was wrong until you can prove that it was done correctly. If you did not rotate the distributor to set the actual timing to 15 that might be the only issue. is jumping all over the place when you experience this condition, it does not In the warm state IAC adjusted to a position of 2 to 10%. Any suggestions? would correct it (as it has for a multitude of other drive-ability issues) but this one little glitch seems out of it's range. The motor has 376hp at flywheel and the car is a stick shift. Intake has been on and off 3 times no change. The IAC going to 30 is normal. But when you have it then you can look for exactly what the IAC is doing at that point, and if there is anything that might lead to this happening. Thanks for any help. The 5-6 times it has happened now have been after the car has been running for at least 20 minutes. I have seen a couple of videos on you tube of the same issue but they don't seem to have found the cure.I hope it is not a computer problem as I have already replaced the entire system because of another problem. The "PC Text" indicates what will be shown on the PC/Laptop data monitor or data logger. Hi Chris, I have a lean stumble on throttle tip in 2-3% tps taking off from a stop light the afr will go to 19afr and the engine will stumble for a split second. You'll have to go back and forth a couple of times to get it just right. Sometimes it sounds like it wants to crank at the start but runs out of gas. If the TPS is 1% or below then the air is coming from somewhere else. If I go any more it will ping. I did notice that when I thought I had it set With the vehicle in neutral, adjust the idle screw until the IAC Position reads between 2 and 10%. But I can tell you that for most people who try this it introduces so much RFI onto the Sniper that it never works right. One additional wrap on the secondary coiled shaft spring is all that's necessary. There's still a very small amount of airflow that squeezes past a closed IAC valve; it's that venturi like sound you're hearing. I think I figured some of my problems outI'll try to explain. mail today. This curve runs fom -40 degrees to 260 degrees, and gradually reduces the RPM along that range. Holley Sniper EFI Troubleshooting Mudford Garage 8.6K subscribers 38K views 3 years ago My Bronco with Holley Sniper EFI was running poorly. Using the handheld, navigate to Tuning > Basic > Basic Idle and ensure your target idle speed is set to the RPM you desire. The team at Holley has designed the perfect solution for your problems. For someone in your position, it will become an indispensable tool in your tool box. I recently had IAC issues identical to what you describe. But once you come off the throttle there is a minimum RPM that the ECU wants to see before it releases the IAC from the park position and that is normally 1000 RPM over the target idle. Fortunately, these are much easier to solve. 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. Interesting question. Its just at low speeds, not sure if its loading up or leaning out. I' m going to put the 3 rd new pump this coming friday.