What should I be looking at to calm this down? Holley Sniper Iac Delete Shut it off and immediately restarted and idle was now 880 with IAC at 8.If this is a vacuum leak I can't figure out what would cause it to go away immediately after shutting down the car and restarting. Kind of cuts into forum time. Thanks for all your help Chris! The throttle position should be zero. Shut off car/restart and it's back to idle at 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). I'm wonder if the iac can cause this. I cut and heat-shrink wrapped the 5V wire and then ran both the signal and ground wires all the way back to the transmission controller. Im in Australia, so stuck the sniper on a 355 Holden engine with CD box. :-). There are a few tell-tale signs that can help you diagnose the problem. The learn function will offset the base fuel table until the closed-loop compensation only requires minimal changes. 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. 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. Once you know that then you can work on those problems. AGAIN This is Intermittent meaning on a recent trip I stopped 3 times and issued occurred once. 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. Ultimately, it is about making the pedal softer, particularly at initial throttle opening. That will happen occasionally, but less as time goes and on and the engine tune stabilizes. But before you adjust the ECU to lean the idle out, first confirm that your fuel pressure is right. )Since this isn't a consistent issue with all Snipers that tells me that different IAC settings tend to make the whistle. Yes, the sound coming out of your Sniper throttle body is a pulsation from the fuel pump that is pulsing the mechanical fuel pressure regulator. I think that your timing is too retarded. I've been messing around for a bit trying to eliminate any possible vacuum leaks. But another thing to consider is adjusting your target A/F ratio. But if the idle is a little bit higher then it doesn't have to jump quite as much in response to the load, and tends to react a little bit more smoothly. So check that timing and I think that you're going to find you need a good bit of advance. While you have over 200 miles on the system, you must realize that in the part of the map where the ECU finds itself during lanches you might only have a total of 5-10 seconds in any given cell. Idle : IAC Rampdown : IAC hold positionChange this by maybe 2% in either direction. I' m going to put the 3 rd new pump this coming friday. It is how the engineers allow you to clear a flood condition when you detect it. The first 250-300 miles were amazing as the Sniper EFI worked flawlessly. Intermittent stalling usually points to radio frequency or electro-magnetic intereference (RFI/EMI). Hey Chris 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. You could install the Holley Dual-Sync Distributor and let the Sniper control your timing. The IAC is hanging open and not really at 0. I have an entirely separate article on Solving RF Intereference Issues. Given the circumstances I would say that it is either the IAC motor itself or RFI but you seem to have ruled both of those out. When I cover it with my hands, it gets quieter. Using a Snap-on variable timing light so this is why I say timing is perfect. I'd suggest that you assume everything the previous owner did was wrong until you can prove that it was done correctly. Please let us know how this works out for you! Also what would you say a desired idle should be for a 3 speed automatic ford? I know this is old, but I bought and installed a Sniper kit in 9/18. I had a customer recently with a high idle problem that he eventually traced to pad plug on one of the vacuum ports. I have certainly seen this before on other fuel injected vehicles when hot. Confirm the placement of all wiring, ensure that the WBO2 sensor is positioned properly, etc. It only lowers to 2-6% when I take my foot off the gas. If i adjust the throttle plate screw in to bring IAC in to proper range say around 7 the engine is running around 2000 rpm. What you are experiencing is rather common. This may require shortening or lengthening a rod. Closed Loop Compensation rises to 100%, Do I just keep pushing it the same way to Your AFR is pegged lean. I installed my Sniper and the engine fired up great. Hey Tommy, we've got at least one thing in common. There's nothing wrong with manual tuning, but at this point that is just compensating for an inadequate fuel map. One thing you need to sync the timing and set the inductive delay. Copyright 2022 Holley Performance Products, Inc. All right reserved. I' m going to put the 3rd new pump this coming friday. So this is my issue ( I did just email Holly). But get that fuel system fixed before going any further. Bryan McTaggart 02/28/2023 news I was shocked to see it at 95lbs!! ?I never had my Carb Cold start RPM any higher then 1600 RPM.THANK YOU. Genuine Walbro fuel pumps are virtually bullet-proof. I emphasize "and" because the transmission controller manufacturer I used had the TPS ground terminated within the harness to the unit's main ground, which I find to be an unthinkable choice. The only other thing I changed was accel enrich but whatever way I go doesn't seem to change anything unless I change it drastically. Jump on board now! Your second problem should be a bit more concerning. Laptop Access No air should be able to pass. There is no sense proceeding until your TPS is at zero at key-on. Last night I tried setting the IAC and had the same problems after it's warmed up. If it is then something is commanding the ECU to open the IAC. Also if I give it a I installed Holley Sniper on three other Mavericks here in Brazil and the problem also exists.I did not make any changes to the parameters, only on Target AFR and the correction on the Idle Speed Curve chart. I have adjusted many settings and eventually mess it up and go back to the original map. I would only play with this if you are finding that the other adjustments I suggested aren't working. Target AFR at idle is 13.8%. If this is the case then I would look particularly close at the IAC hold position and IAC ramp start.Let us know what you find and what works for you! This minimizes installation time and packages really well on a diverse group of engine applications. But he kept having problems so eventually he did a complete check and then he found the problem. My IAC and TPS show zero when it does this. Any idea's? Stupid question, but where do I see if it's entering Learn mode? Nothing against Holley's method but I need to keep things simple and I do that by eliminating the effect of the IAC entirely while getting the idle speed adjusted. Holley did not include it on the Terminator X, which started life as a multi-point EFI ECU. Throttle body mounted ECU - no extra boxes to mount. While this video is not meant for the Sniper EFI user it does provide a great overview of how your ethanol tuning adjustments must be made not only to the base fuel map but to the other configuration settings. Put a strong piece of tape over the IAC breather hole--duct tape or something that couldn't possibly be sucked into the throttle body. Reducing that a bit will help. I didn't find your site until I was having trouble. Price Point: $, Advanced throttle body injection systems capable of transmission control and more. I'm new to the efi thing and any help would be seriously appreciated. Pw. No, the idle speed curve setting isn't something that you normally worry about--and especially not down at minus 40 degrees farenheit. And if you're going to go this route I'd recommend that you switch from "Simple" (3 A/F targets, one each for Idle, Cruise, and WOT) and go to the 2-D Table I had a customer who struggled to understand that. That's what you're seeing. The progressive link can be a great solution on standard (non-Stealth) throttle bodies but I would install this LAST after everything else is working perfectly. I was looking at a data log from my truck earlier this week and noted that at idle my IAC was zero. I followed the instructions and set the IAC to 2-9% when warm with idle at 850 RPM. I appreciate everything you are saying. Can the return line be an issue?I have had 2 faulty gpa-4 255 walbro pumps go bad. When I put it in gear, it drops so low that it will stall if I don't add throttle. The team at Holley has designed the perfect solution for your problems. = 2.34 Honestly, I've never seen this happen but if the butterflies were misaligned on the shafts it could allow too much air to enter. Or is there something else I should But after sitting static idling for a little bit, the IAC goes to 100% & stays there. In the datalog the engine is running at 1400 RPM, TPS is zero, IAC is zero, CTS is 185F but it's in Open Loop. Get a solid feeling for where it is when the engine is warm and the idle speed is correct. 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. Drives just fine but won't stay running unless I keep my foot on the gas. Cheers Darren. That changes almost instantly as the engine revs.Since the learning algorithm requires some time exposure to a certain condition to make larger changes, that half-second makes only the smallest impact. 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. Your issues are likely related to one of these two things. I followed the instructions and set the IAC to 2-9% when warm with idle at 850 RPM. Running the vacuum advance and of course I time it disconnected. Ok, so there are a couple peculiar things going on here. You can re-enable this after you have completed this idle speed adjustment process. What is it supppse to be at idle and while driving under heavy acceleration? 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. :-). The headache is the Acceleration Enrichment. They also recommended that their ground be spliced into the Sniper ground as close to the Sniper as possible. He is able to get it to start by quickly depressing the accelerator to at least 60% and releasing. Anyway I have a 327 sbc in a 1987 Monte SS with a T5 5 speed and 3:73 posi rear. Now that you've installed at least four Snipers it is going to be imperative that you learn to create and read datalogs. 34K views 1 year ago Holley Sniper How to Set The IAC Idle air Control in 5 minutes or less. It works instantly for him.If that fixes your problem then you have a starting place. My issue is that the TP% will not reset with key cycle and its idleing at 9% TP. I will turn it up some more.Is this something that the ECU will learn? To start viewing messages, select the forum that you want to visit from the selection below. Without it you are working in the dark. You can disable the idle spark control at the locations below. Any help would b great. We offer some tips to help with that. https://www.youtube.com/watch?v=2JpHlS1ymBc, If this is your first visit, be sure to
You're going to have to get this fixed or it's going to cause even more problems than the high idle. A couple of those and you should feel it getting better. One of the signs of a vehicle with a rough idle is a faulty Idle Air Control (IAC) Motor. The solution is to either lower the IAC hold position or increase the RPM above idle to start ramp (default is 1000 RPM). After manually making the sensor go through the full range a few times, I reinstalled it and now my TP will read anywhere from 0% to 4% when I key on. That way you can get into that part of the table that needs tuning, and you can watch your learn numbers grow. Just add 5 or 10 degrees of advance and see if it doesn't idle better. However, it is a good question so I thought I'd throw a few bits of info out there that I think might help.First, I believe that you may have a basic misunderstanding of what is being referred to sort of generically as AFR. That will at least tell you something. Fuel Flow lb / h = 12.1 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).