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. While adjusting the screw if the TPS position reads begins to read higher than 0% cycling the ignition switch will recalibrate the TPS back to zero. :-DStill, I hate to leave someone hanging so I'll try to help. I think I figured some of my problems outI'll try to explain. holley efi. Interesting question. I will turn it up some more.Is this something that the ECU will learn? I can have it working fine (5% to 10% at target idle at operating temp.) About two minutes after I get it set at 850 & 5%, it has progressed to 100%. If you go too high then the motor will not return to your target idle when you come off the throttle. 90% of problems, (INCLUDING MYSELF) could be answered/fixed by just reading the instructions. So, if pressing the throttle is making it start, it's because you're flooded.Which is consistent with your rich idle condition comment, right? :-). Holley sniper, bogging/ losing power "NOW FIXED" However, I did have another fellow who contacted me that claims he went through three units before he could get one that would talk between the ECU and the Monitor. sniper Installation 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! It appears that I could now use the dongle and a laptop to custom tune for idle issues if needed. Well, it turns out that with the current firmware this throws the IAC control into a bit of confusion. back to trying to zero down an idle. Holley Sniper EFI Self-Tuning Master Kit - Black Ceramic Finish The following are status commands and diagnostics for sensor and various parameters in the Holley software. 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. Price Point: $$$. So, this is what it takes to put a Sniper on a small-block Ford. It will need to see it again and again. Explained: Holley EFI Sensors and What They Do I recently had IAC issues identical to what you describe. Shutoff engine wait 30 seconds, turn key wait for display to come up, start engine. Clearly, something is changing. 400 engine, C6 3 speed automatic, with standard canister coil for ignition, and You have to remove all hoses in order to debug the problem. Idle quality is great, RPM is good, sometimes IAC is jumping around from 35 to 60. Holley Sniper EFI 550-552 Holley Sniper EFI Autolite 1100 - Gold The Street/Strip and race cam setups tend to be too rich initially. I' m going to put the 3 rd new pump this coming friday. Using a Snap-on variable timing light so this is why I say timing is perfect. Don't be surprised if one or the other is slightly open. When you first posted this I had no idea how to respond. If I keep the rpm's up it does fine but my clutch can't keep up with this for long.Also when I cover the IAC port the engine dies. Camshaft is M-6250-B303 .480 lift intake & exhaust, duration at .050 is 224 degrees for intake & exhaust. The engine runs beautifully, with perfect idle at 650 RPM, but every now and then I hear the IAC give a sort of "snap" and the idle is at 1200 RPM. These are "transitional" cells, and you really have to make the effort to learn in these areas of the map. I have driven it a few times maybe 100 miles or so. Thanks in advance for any advice. I followed the instructions and set the IAC to 2-9% when warm with idle at 850 RPM. If I were there in person I would test the function of the IAC (see this article.) I have adjusted many settings and eventually mess it up and go back to the original map. idle at 1100 on the "stock" file it's better with street strip.The IAC counts will be at zero. I would suggest you take a look at that if you haven't already. Kind of cuts into forum time. If you set the RPM above idle to start ramp too high, then it may not ever get down to the RPM above idle to re-enable. issue. ?I never had my Carb Cold start RPM any higher then 1600 RPM.THANK YOU. Then you can take a close look at the IAC and see if it is opening. The throttle position should be zero. In this short video you learn to replace the IAC. WIthout knowing quite a bit more it will be more than challenging for you to identify the problem and solve it.Fortunately, Holley provides their amazing Sniper Software. Once you so this, and after you have your CAN-to-USB harness attached to your laptop with the Sniper software, you can see precisely the cells where the system is operating when the bog occurs. If there is an issue with using the Sniper EFI TPS signal, is there a remote TPS or an adaptor for the Sniper EFI that allows the TPS signal to be accessed for the transmission. Copyright 2022 Holley Performance Products, Inc. All right reserved. It has a lightweight centrifugal spring kit installed so I reach total timing around 2500 rpm. This can cause the engine to run rough and may even lead to engine damage. I appreciate everything you are saying. When you set the Static Timing to 15, what did you read with the timing light? Don't try to correct for the fuel. 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. The 5-6 times it has happened now have been after the car has been running for at least 20 minutes. I'm Having trouble with the Sniper on high Idle. Resistance results in heat and heat results in more resistance. Bryan McTaggart 02/28/2023 news Sniper is still learning so it will continue to improve.Second, you may have heard the phrase, "correlation is not causation." 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. The distributor was loose. I did all of this before seeing the link you sent. At low levels RF interference will often reset the ECU so quickly that the engine will not stall. Once it decides to come back down, it does so with no issue. Setup: 1965 Impala SS; ZZ6 Crate Engine, EFI Distributor. 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. I am having an idle issue (other than that is absolutely perfect). I.e. 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. The only way to confirm RFI problems is by doing a data log. 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. The 10 step set up on your page set my idle perfect and iac perfect a very consitant 700. Also what would you say a desired idle should be for a 3 speed automatic ford? Therefore The iac will always be at 10% now, correct? Holley Idle Air Control Motor Idle Air Control Motor Fits the Following Applications: Sniper EFI 90 mm, 92 mm, 102 mm Throttle Bodies Digital Pro-Jection Systems Avenger 4-bbl TBI Commander 950 Terminator TBI 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. 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. Once we recognize that, the next step is to narrow down all possible sources of additional air until we discover the cause.Start by keeping an eye on your IAC number. This may sound crazy but I'm going to jump out on a limb here and say you don't have an idle issue--you have a timing issue. Going in the direction you did (higher) is going to reduce the acceleration fueling that the engine sees. :-). After talking to Holley tech, I replaced the factory regulator and problem solved.The regulator had what appeared to be a film or something almost clear embedded in some of the screen, maybe from factory or from install, but that was my issue.PS : this page and other forums have helped me a lot. Though it started and ran good, it was dumping fuel and would not lean out to AFR set points. All times are GMT-6. Then Friday night as I was driving home, the car started acting up. That is the IAC hold position. The symptoms I had was a low cold start idle and going lean coming to a stop. Pw. Thank you for any advice. Any idea's? If you've been running a filter then you have to wonder if you have a legitimate Walbro pump.If you install a new pump and the noise is still coming from the Sniper EFI System then only the dealer who sold you your system can help you. And the only way to be positive about that is with a gauge.Unfortunately, the Sniper does not provide an input for an electronic sender so the next best thing is an analog gauge. It will still change a bit with weather changes and when you get into infrequently-used sections of the map, but it's nothing to worry about.Regarding your idle speed immediately after start-up, that is determined by your Idle Parked Position. It sounds like you need a bit more of a fuel squirt on acceleration, Brett. Can the return line be an issue?I have had 2 faulty gpa-4 255 walbro pumps go bad. Suddenly, the engine accelerates alone, hears a great deal of air being sucked in, These aren't generic newsletters either but instead personalized emails. I think you'll be all set! Physially manipulating the linkage by hand will generally reveal if you have a sticking linkage that is preventing the TPS from returning from zero. To get it to idle the tps is at 2-3-4% even with linkage disconnected and a return spring installed. I have a Holley Sniper EFI with HyperSpark ignition. After only running for about 15 minutes or so the system starts to fail stalling the motor. Simply turn the idle speed screw on the linkage in until the throttle plates open enough for the idle to increase. Hope this helps! There's nothing wrong with manual tuning, but at this point that is just compensating for an inadequate fuel map. Installed sniper on 65 galaxie. I installed my Sniper and the engine fired up great. Hello Chris. Maybe Holley will add Fuel Prime Multiplier to Terminator X later. and go to restart warm, it catches starts for a flick of a second, drops to a stall, or sometimes will catch its self and start. There is no sense proceeding until your TPS is at zero at key-on. the issue 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?
holley sniper efi iac problems