No matter what do, my idle will not drop below 1350-1400 RPM when the engine warms. No problems with either cold or hot starts. Hello Chris. Ive tried setting the prime setting above 150 but it wont take, it always goes back to 150. In addition to avoiding this particular problem, the total solution is much better. The Sniper EFI replacement throttle body for Autolite 1100 carburetors will be right at home on most early in-line 6 cylinder powered grocery getters or weekend cruisers. I am new to the EFI scene but want to learn. Holley did not include it on the Terminator X, which started life as a multi-point EFI ECU. Should the iac% fluctuate? when things aren't working and this provides just that. 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. What could be the cause? I've tried repeatedly re-creating the scenario in hopes that the E.C.M. Your AFR is pegged lean. The Sniper ECU can use the timing to help maintain the idle speed and that will definitely be useful in that transition from Park/Neutral to Drive.If you don't have ECU-controlled timing, or if you do and it's not fully compensating, it may be necessary to increase your target idle slightly. After a complete cool down it will do the same thing. :-). 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. If you have a bellcrank in your throttle linkage, ensure that the linkage is not engaging the bellcrank at an angle greater than 45 degrees at either end of the throw. If I'm driving along and pull up to a light and leave it in gear it idles just fine but it seems not to be able to compensate if I put it in neutral and then back and drive. The idle will not return to the set value.The second issue is the same as the first but the motor will stall out. 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. If you look down and your TPS is 2% then either your throttle is stuck slightly open (which itself will cause the idle-up) or RFI riding on the TPS signal has caused the ECU to see the throttle as open and, as a result, open the IAC to the hold position. $107.95. 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. In the warm state IAC adjusted to a position of 2 to 10%. the issue Let's start by not assuming anything. One of the great features of Holley's Sniper is the ability to set your air/fuel ratio (AFR) where you want it. As always, I recommend great restraint in changing any of the parameters until a significant amount of learning has taken place. Once you know that then you can work on those problems. Hello, I am having a tps and idle issue. How can I adjust the startup speed down to about 1400 RPM? 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. But, if the idle is so high that it is making you crazy then you might try dropping that number just a bit. Turn the idle speed screw on the primaries in about 2-3 turns after it makes contact with the linkage and starts opening the primary throttle blades. Just wondered if you've ever run across a system not powering up? And all too often we don't take that extra step of using a piston stop to ensure that the timing pointer is on zero when the engine is truly and exactly at top dead center. Bottom line ismy first one must have been faulty. Now, in my lifetime of experience with Holley ECU's that seems unlikely, but this guy sounded really sharp and had nothing to gain by convincing me of his dilemma. All times are GMT-6. But as you see from the recent revision I did above you seem to be having a fixable issue. It turns out that some of the Snipers are shipping with the minus 40-degree setting drastically lower, as shown in the following image. However based on your reply I connected the Fuel Pressure gauge and You can drop it down and you will find it will behave more like you expect. 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. It's not necessary to drive it that way. and if you do run into any problems then, yes, the plethora of tunability adjustments available through either the handheld or the Sniper Software will certainly be enough to get you right where you need to be! It sounds like you need a bit more of a fuel squirt on acceleration, Brett. After a stall the car will restart but will be in a high idle. Or, at least, it should. I have an entirely separate article on Solving RF Intereference Issues. 2. An undersized or partially plugged fuel filter is a classic EFI installation mistake. If idle drops below 800 it wont come back itll chug around 300 rpm for a few seconds then die. That is certainly not normal! The small rubber plug had a leak. issue. I am having an issue with the IAC on the Sniper. They are prone to be inaccurate. It then idles up from 750 to 1100. When I drive with warm engine the IAC is at 30% when pushing gas, but shouldn't it be at 0%? Do you have a PCV on the engine? 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. Using the handheld, navigate to Tuning > Basic > Basic Idle and ensure your target idle speed is set to the RPM you desire. is jumping all over the place when you experience this condition, it does not Start with the most gradual throttle input you need to launch well, then slightly increase until you feel some stumble. Does anyone have photos of this additional return spring they installed? I' m going to put the 3 rd new pump this coming friday. knowledge with the sniper efi setup. That is not something I'd ignore. that my Air/Fuel ration was 15:1 and I believe the target is 13.5:1. If this is the case then some adjustment of the linkage or the butterfly plates themselves is necessary. I appreciate the help youve given to everyone as it continually helps me! I'm Having trouble with the Sniper on high Idle. I will a, Scott has been very helpful and informative on guiding me through the purchasing and installation of my terminator X max system. I'm wonder if the iac can cause this. I also noted that after some time, I could change those values as I saw fit. If you find that adding 5-10 degrees of advance helps then it's time to do reconfirm TDC. 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? 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. check out the. My problem is low idle. This curve runs fom -40 degrees to 260 degrees, and gradually reduces the RPM along that range. I've been trying to correct that 1% small issue/annoyance. Super helpful and knowledgeable. I have tried your 10-step idle adjust and ive adjusted the idle curve. When I see that your TPS is 1%, that tells me that you may have an RFI problem. Wish I had bought my sniper from you, but unfortunately didnt. I have one customer who is having some similar issues and his AFR is down at 9.6:1 when it won't start. A simple remove & clean will remedy this . That is the IAC hold position. Drive great and idles perfect at stop signs. 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. Switch power to the Sniper on and crank the engine. Comp. 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. Car has run perfect every time and has never hesitated or stalled since. Thanks Again for your help. The distributor was loose. I haven't driven it for the 30-40 minutes like the several times it idled at 2200. 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. (Plus they it just looks way cool in your engine compartment!) If you get into the practice of hearing all three of these sounds you will know if you have a problem even before you turn the key to crank. It's pretty hard to get the header tubes glowing at idle with a lean AFR. Chris, 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. Resistance results in heat and heat results in more resistance. lower until I turn down the set screw. Key, I believe, in this success is solid connections, resistance-free signal and ground paths, and solid RFI rejection. May God's grace bless you in the Lord Jesus Christ. All in all, considering the system has been installed for less than 2 hours drive time we're BLOWN AWAY at how quickly it is "learning" this engine. Thank you very much. We do that but most places don't. You may have to register before you can post: click the register link above to proceed. When I put it in gear, it drops so low that it will stall if I don't add throttle. Somehow air is entering the engine that was not entering the engine when you originally set the idle speed screw. I have driven car about 200 miles. ps. IAC percentage is 5 to 10% when idling with fans on, What you're experiencing is the delay time between the ECU sensing the additional load and the IAC actually increasing the RPM. However I do have a couple of issues I hope you can help me resolve. If that tested out okay then I can really guess that there might be some sort of intermittent, temporary RFI. It works instantly for him.If that fixes your problem then you have a starting place. Software: Idle > IAC Settings > Idle Spark, Handheld: Tuning > Advanced > Advanced Idle > Idle Spark, After completing this 10-step process, if the temperature displayed on the handheld is still above 160 degrees the engine should go right to it's target. It's all part of the adventure! I did buy the Sniper from you guys and the service was fantastic. Please give this a try and let us know how it works! A couple of those and you should feel it getting better. This may require shortening or lengthening a rod. But get that fuel system fixed before going any further. I would continue checking the electrical connections along the fuel supply. A couple of possibilities that come to mind in order of likelihood: Im having an issue with what I think is the Iac. If you go too low then it may stumble or even stall when coming off of throttle. If I go any more it will ping. Usually it wont stay on 0% very long and soon changes to another number like 1 or 2%. Holley EFI Electronic Fuel Pressure Gauge, article on choosing between Sniper and Terminator X throttle body solutions. One thing you need to sync the timing and set the inductive delay. Contact whomever sold you your system or Holley directly. My car will now start when its cold, but after about 30 seconds the idle drops down and begins to run like crap. Holley Sniper EFI Troubleshooting Mudford Garage 8.6K subscribers 38K views 3 years ago My Bronco with Holley Sniper EFI was running poorly. You will have to do this until the TPS stays at 0% when the throttle is closed. Then why don't you Get On The List for Emails Straight From Our Pro? Ensure all your sensors are displaying proper values. 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. Not to bandstand here but this is the point when where you bought your system is so important. I have a set of 8.8 Accel Rfi suppression wires on it. Next, clean the IAC and all related parts with brake cleaner. As soon as I got the new one installed and wiredit fired right up and did everything it was suppose to do with no issues. Since a key cycle resets it to 0 and out to 30 or wherever Commanding the engine to automatically increase speed when switching into drive is a little scary to me though. 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. I have a 406SBC that does most everything right with this sniper setup. 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. When the system is up and running the fuel pressure regulator inside the Sniper is making a rattling sound like a shaking a paint can. The IAC reads 36 when at idle fully warmed up. There's nothing wrong with manual tuning, but at this point that is just compensating for an inadequate fuel map. Ive had an idle at neutral as high as 2400 rpm. And your understanding of how the throttle position affects idle is exactly correct. I called support line he said he would have to look into it and call back. Ok, so I'm stumped! Last night I tried setting the IAC and had the same problems after it's warmed up. Turned it off and on again. Maybe Holley will add Fuel Prime Multiplier to Terminator X later. The motor has 376hp at flywheel and the car is a stick shift. However, I have what I will call a whistle at a throttle position on 35 - 50. 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. Thanks so much for reading! I did all of this before seeing the link you sent. The Sniper even has a feature that allows it to use the idle timing to control the idle speed. It will need to see it again and again. When I covered the IAC with my finger, the RPM dropped so low it stalled. All times are GMT-6. Holley Sniper Iac Delete Check the Distributor Tach Connection to the EFI.