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! Glad to hear that things are working well! I am Japanese who attached Sniper EFI. Duty Cycle% = 3 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. !I called Holley today, and before I could even described the symptoms the It wont fire up. 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. Once engine is warmed up been driving for awhile. I think you'll be all set! Thanks, That is an strange situation. Thanks for your very detailed question! Sorry for all the questions, new to the efi world. Good luck! The biggest issue is these problems are intermittent meaning they do not occur all the time. If you go the other way then you might find that the IAC zero's out when the fans are off. It shuts off when coming to a stop sign, at any cruising speed and romdomly at idle in park but never when excelerating. If you datalog the Sniper ECU and see multiple overlapping traces for the same signal, you likely have RF-induced problems. In the setup, I set the hot idle for 850. I have adjusted many settings and eventually mess it up and go back to the original map. New install, when in setup wizard TPS says 90 percent and I checked the linkage and butterflies. Pw. Hello Chris. At any rate, once the setting was moved up, the RPM jumped right to the target RPM and was solved. Camshaft is M-6250-B303 .480 lift intake & exhaust, duration at .050 is 224 degrees for intake & exhaust. 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? and when I close the IAC's hole with his finger, the engine is normal.The data on the touch screen I see are:AFR, A / F = 35.6 Hey Chris Two months fighting, cursing, not getting any help from Holley OR the forum, and a stupid little tin plate. the gas it catches itself and runs fine at slower speeds. Simply use your handheld controller and go to the Tuning > Advanced > Advanced Idle > Idle Speed screen and click on the Idle Speed Curve function. Closed Loop Compensation rises to 100%, Do I just keep pushing it the same way to Ensure there isn't a vacuum leak causing the IAC Position to drop to 0%. If you see that the ECU is commanding the IAC to 0 but there is air entering the IAC port then it's time to refer to my article on IAC Testing Procedures, Hello,I installed my sniper system on a 65 mustang, with a 302. Good luck! 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. Or is there something else I should Sniper setting is Stock camshaft. Idle Tuning is a very important part of tuning any EFI system, especially our self-learning units like Sniper or Terminator X EFI. However, whenever you start changing things, you can get into a chain reaction. That will at least tell you something. The first 250-300 miles were amazing as the Sniper EFI worked flawlessly. Ilike a few othersam having idle issues. Idle quality is great, RPM is good, sometimes IAC is now between 2 and 5 exactly where it should be. Your AFR is pegged lean. At some point you come upon problems that evade the easy answers and this is a good example. Hope this helps! I followed the instructions and set the IAC to 2-9% when warm with idle at 850 RPM. Chris I am having a little different idle problem I did your -40 thing and that help with high idle but my problem is it idles fine until I drop it in gear and it stumbles a couple times catches up and then idles fine again. You'll be amazed at how much of this just "goes away" when you drive it enough. Then your low idle problem will go away. Even though the Sniper's fuel map is programmed to provide the correct amount of fuel via injectors spraying at 60 PSI, if the pressure is jacked up to 90 PSI the wideband sees that you are rich and faster than you can even detect it audibly lowers the duty cycle to inject the correct amount of fuel. The team at Holley has designed the perfect solution for your problems. The warmer the motor, the higher the idle will be at this point. Thanks for any help. No power at the programmer and no fuel pump running. Hot start it most of the time wont start unless I give it a little throttle. I straightened that out, got it running and that's where it goes downhill. Really appreciate the amount of learning im getting off here. There are a few tell-tale signs that can help you diagnose the problem. Every time though I can turn the car off and restart and it settles at 850 with IAC 2-4.The thing that has me puzzled is how the with the only difference in condition of the car being the restart, the idle is "fixed"Any clues on where to look next please let me know. The distributor was loose. But I think it is safe to say that you are now at a point were some manual tuning is a good idea. An under-sized filter will allow part- throttle operation but fuel pressure will drop at WOT and run very lean - perhaps surge under power. 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. For someone in your position, it will become an indispensable tool in your tool box. Perfectif you have the original synchronous linkage. Then why don't you Get On The List for Emails Straight From Our Pro? I also noted that after some time, I could change those values as I saw fit. Handheld shows plenty of fuel so I dought it's an issue there. To finish, I rather tightly twisted the TPS signal and ground wires all the way from the controller to the Sniper TPS and very carefully routed them away from sources of RFI. It only comes back to normal if I turn the engine off and on again. Try it! Overview. Ok, so there are a couple peculiar things going on here. Holley will take a look and tell you you have RFI and wish you good luck in finding it. Hello Chris. 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. One of the signs of a vehicle with a rough idle is a faulty Idle Air Control (IAC) Motor. EFI Systems based on Holley's world-class Dominator and HP ECU's. Car has run perfect every time and has never hesitated or stalled since. If i set the idle to 750, the only way i can get it there is to turn the idle screw all the way out but then its at 0 iac. I would continue checking the electrical connections along the fuel supply. I've been trying to correct that 1% small issue/annoyance. If it is then something is commanding the ECU to open the IAC. Hopefully replacing the pump again will resolve both issuesWhoa. It is made by one of the biggest names in fuel filters and sold under the Parts Master label so it is quality and great price in one. 2. lower until I turn down the set screw. Hi Chris thanks in advance for any tips. During after-start idle, the idle will jump up to about 70% if the engine is cold, stay there about 4 seconds and then ramp down to the target idle speed for the current engine temperature. Tuning > Advanced > Adv Idle > IAC Startup You will have to do this until the TPS stays at 0% when the throttle is closed. Copyright 2022 Holley Performance Products, Inc. All right reserved. 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. Throttle Tip-In puts you in a part of the fuel map where you stay for only milliseconds at a time. Am I missing something. *Possible delays due to Covid-19 click for more information. You are aware of the idle-up problem. Then a little faster--until bogs at that level work themselves out. The fuel pump is mounted under rocker panel as low as possible and far away from any heat. Running the vacuum advance and of course I time it disconnected. :-). It has a lightweight centrifugal spring kit installed so I reach total timing around 2500 rpm. 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. Except at idle. I will turn it up some. to. Strangely, what I've seen is that it idles too lean as the injectors are effectively shut off.Thanks again for the follow-up and glad to hear that everything is working well now. This happens no matter how much I adjust the idle screw. idle at 1100 on the "stock" file it's better with street strip.The IAC counts will be at zero. But you've got to find where air is getting into your engine.The reason it's going up as high as 2400 RPM is because once you press the throttle beyond 1% the IAC opens to the park position. 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 Capability Range: Moderate Now it registers zero and I have good idle but it will not register until it hits 60 and up. Due to when the pump i'm using now makes a loud howling noise when it gets ran for awhile and it gets at a 1/4 tank of fuel or less. Fought a high idle issue until I changed your idle speed curve fix along with dropping the IAC hold to 10%. He said they have been having an issue with these lately. Idle quality is great, RPM is good, sometimes IAC is now between 2 and 5 exactly where it should be. 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. May God's grace bless you in the Lord Jesus Christ. Thanks. The car would idle, I could hit the gas rev the car up and it ran great I also noticed two nice black spots on my garage floor from the exhaust. Others might require 60 RPM. Some advanced conceptsIf you have the Sniper Can-Bus to USB Adapter, you can connect your laptop, open the software to the learn table, and get a visual for where in the table you are experiencing the lean bog. Holley Sniper IAC Surging???? Fortunately, these are much easier to solve. 90% of problems, (INCLUDING MYSELF) could be answered/fixed by just reading the instructions. Has a good size camshaft cant find any vacuum leaks. 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. OK, I did the baseline idle speed screw setting. Contact whomever sold you your system or Holley directly. What I would recommend is getting somewhere that you can spend a significant amount of time doing starts. SNIPER EFI TO HOLLEY DUAL SYNC HARNESS Part# 558-493 $34.44 Qty: Add To Cart Idle Air Control Motor Replacement Idle Air Control (IAC) Motor for Sniper EFI TBI Systems, Sniper 90/92/102mm Throttle Bodies, Terminator TBI, Avenger 4bbl TBI, HP 4bbl TBI, Commander 950 & Digital Pro-Jection Systems Part# 543-105 $71.72 Qty: Add To Cart first attempt but as it tries to idle down to the target RPMsit can never even % = 49 Chris, And yes, monitoring the fuel pressure is the right answer. Also what would you say a desired idle should be for a 3 speed automatic ford? Very annoying ended up being simple my rear plates would stay open constantly it was driving me nuts I'd let off the pedal idle at 1300 blip the throttle a few times finally come back to 850. I have driven it a few times maybe 100 miles or so. I can drive it a bit but pops through the throttle body when pulling out from a stop (4 speed) and sometimes in the exhaust out on the road. But if you will just advance the timing at idle and see if it makes a difference then that will tell you what you need to know. Find a lower price anywhere and we'll beat it by 5%! such high fuel pressure. I drove it a bunch more yesterday afternoon/evening and the same thing happened several times. Don't make any changes more than about 10% and keep the same basic shape as the original (High/flat below 20 degrees, sloped downward up to 180 degress, and then flat again above that.) That is likely just confusing the issue.Instead, choose whichever setup most resembles your camshaft and stick with that. nothing stays steady. But as you see from the recent revision I did above you seem to be having a fixable issue. 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. Yes its at 95lbs, needless to say he promised a new regulator would be in the After the start process, If the idle speed is higher than the target idle then the IAC should begin closing as long as the TPS is below 2%. 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. My issue is that the TP% will not reset with key cycle and its idleing at 9% TP. The AFR was pretty consistent around 13. What you are experiencing is rather common. Even at 0% it's sucking a bunch of air through the IAC port. The 5-6 times it has happened now have been after the car has been running for at least 20 minutes. 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? This may require shortening or lengthening a rod. Everything was working perfectly and I shut off the engine. Replacement Idle Air Control (IAC) Motor for Sniper EFI TBI Systems, Sniper 90/92/102mm Throttle Bodies, Terminator TBI, Avenger 4bbl TBI, HP 4bbl TBI, Commander 950 & Digital Pro-Jection Systems. I am new to the EFI scene but want to learn. I will a, Scott has been very helpful and informative on guiding me through the purchasing and installation of my terminator X max system. Is that normal? I put it in neutral and the idle RPM had increased to 2100-2200. Is this an issue to worry about? I think that the more important point is that Holley kept sending him units until everything was working. I will turn it up some more.Is this something that the ECU will learn? I have a Holley Sniper EFI with HyperSpark ignition. The problem was RF interferance . Or alternator? Cheers Darren. Good afternoon Chris, thanks for taking the time to help all of these folks that didn't purchase from you- myself included!The issue I seem to be having is at idle in both park/neutral and drive. Coming home from work today it was much warmer and took a little longer due to traffic. However, I can't think of a single one that was because of low vacuum. I have never seen issue when CTS is below 120 degrees. It has gotten a little better after I drove it for three hours today.I want to save the Kik because if I get this working good then I would like to add A C and use the kick for it.Motor is Mopar 360 with mild cam and automatic. 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. Holley Sniper IAC Problem 04-26-2018, 11:30 AM Hello. The solution is to either lower the IAC hold position or increase the RPM above idle to start ramp (default is 1000 RPM). So as much as I can I have been taking off real slow and let it fall on itself to try to learn and its not learning its way out of it. 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. This is extremely unreliable afrer warm. Have you confirmed your fuel pressure at idle is 60 PSI? The IAC reads 36 when at idle fully warmed up. 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. When I put it in gear, it drops so low that it will stall if I don't add throttle. is jumping all over the place when you experience this condition, it does not Usually it wont stay on 0% very long and soon changes to another number like 1 or 2%. And Earl's makes a fantastic little 100 PSI gauge. There is a chance that the IAC is open but displaying 0% so start by putting your finger over the IAC opening. Without it you are working in the dark. Hi I wish I had bought from you but I didn't find this site until now. Even though you think your timing is perfect I'd suggest you try cranking about 5-10 degrees of advance into the distributor and just see if that doesn't work better for you.Remember this: adjustable timing pointers go out of adjustment and harmonic balancers slip. I go into much more detail about that in this article on startup tuning. The broad consensus has been that the Sniper is an amazingly straight-forward install and starts and tunes as expected. MAP Sensor. Capability Range: Advanced There are six different acceleration enrichment tables that you can tweak and that may be the way to go. If you do find you have RFI issues then I've written an . Of the two options, I generally recommend the self-learn. That is what I really respect about Holley. I'm thinking it could be the fuel pressure--- since I have a new Spectra EFI tank and there's been some reports of the interior coating coming off and gumming up the pump however the sniper display DOES NOT show fuel pressure.the Sniper DOES measure fuel pressure on its own - i've confirmed that with holley techs as they told me to purchase the fuel pressure gauge that can just hook up to the 1 wire gauge harness from the Sniper. Now it's at 5% on a big cam 440 Mopar. In some cases, you may only be able to put as little as 10 RPM between the hard idle and the target idle. Ultimately, it is about making the pedal softer, particularly at initial throttle opening. I have tried your 10-step idle adjust and ive adjusted the idle curve. Both Sniper and trans controller grounds were direct to the battery ground, as they should be. (It should be at or near 60 PSI at idle. 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. I'm going to jump out on a limb here and say you either don't have adequate fuel flow or pressure. You might have a bad O2 sensor, really bad exhaust leak or a problem with the ECU. I have installed my Sniper and the car runs great. :-). 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. A couple of those and you should feel it getting better. If you find that the IAC is more than 8 percent, repeat this process and instead of shooting for 50 RPM below your target make it only 40 RPM below the target idle speed. When I start the motor I have to push on the accelerator pedal for the motor to start. It sounds like you need a bit more of a fuel squirt on acceleration, Brett. So I had my Idle set up perfect, with idle timing control off and engine hot the IAC was right at 2-4%. 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. Next, clean the IAC and all related parts with brake cleaner. Bolt-on carburetor style EFI for your classic car or truck. As always, I recommend great restraint in changing any of the parameters until a significant amount of learning has taken place. The IAC going to 30 is normal. Properly configured, the Sniper does a fantastic job of responding to the transition from Park to Drive. This is more of a bit of a reality check. I'm running a 408 sbc. 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. 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. That, on top of your air leak, is allowing the engine to idle at 2400 RPM. The symptoms I had was a low cold start idle and going lean coming to a stop. But I wanted to go ahead and answer this so that it would make sense to someone who might not go that route.I think the first thing I'd do is try another pressure gauge.