Jump on board now! :-). I will a, Scott has been very helpful and informative on guiding me through the purchasing and installation of my terminator X max system. The Sniper EFI system looks at the closed-loop fuel compensation required to reach your target AFR. Could the IAC be broken/malfunctioning? Not to bandstand here but this is the point when where you bought your system is so important. :-). When you open your IAC to 30% you are naturally going to have a high idle condition. Hi Chris. Initial Baseline Idle Speed Screw Setting, http://forums.holley.com/showthread.neral-IAC-Info, http://documents.holley.com/199r11031r.pdf, https://forums.holley.com/showthread-Idle-Solution, If this is your first visit, be sure to They always responded to my questions with guidance that helped me choose the right system for me. Ok, we have enough Sniper systems out there that I thought it would be a good idea to create a posting on challenges that might arise during installation. 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. 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. is jumping all over the place when you experience this condition, it does not 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. Ive had an idle at neutral as high as 2400 rpm. The Sniper Quick-Start Manual provides the following instructions for setting the idle. 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. It will drop down to 400 RPM then climb 500 and then shoot to 900 and then come back sometimes two or three times then catch it self an idle just fine again. I have not heard of this. But I am having troubles.When stepping on the accelerator slightly with idling, it will be 2000 RPM all the time. There are a few tell-tale signs that can help you diagnose the problem. View Holley Sniper EFI Self-Tuning Kit - Shiny Finish. Start engine let it warm up to 160, learn mode is learning. Relatively new Sniper EFI install on a '69 Mustang 302. If that happens then follow my 10-step process shown above. Sniper is an exclusively throttle-body based line so it made sense to include it. Others might require 60 RPM. 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! Ilike a few othersam having idle issues. 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. He has walked me through every question Iv. Should it not do the opposite and do this on a cold start not warm. Target AFR, A / F = 13.5 Common killers: No filter in front of the pump, reverse wiring, driving with PWM voltage, running at dead-head pressure.Since it sounds like your pressure is right, and since the Holley system doesn't provide a PWM voltage, that pretty much rules out everything but the lack of a filter. So this is my issue ( I did just email Holly). Since a key cycle resets it to 0 and out to 30 or wherever In that case, and if you have an EGR valve, I might be suspicious of something going on there. I set the AFR at 13.5 and all is good now. That is a good thing.I don't have a specific target RPM but always encourage automatic transmission users to bias the idle just a tiny bit higher than what you might otherwise. You could go either way.. If I put the vehicle in gear the idle gets higher with temp. Im in Australia, so stuck the sniper on a 355 Holden engine with CD box. 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). The problem I experience is that after driving for about 10-15 minutes, the car starts idle to high. We're never going to fill up your email box with nonsense. It appears that I could now use the dongle and a laptop to custom tune for idle issues if needed. When you key on, you will hear three distinct sounds: The ECU initializing the IAC, the fuel pump priming, and the injectors firing their prime shot. We are running a Sniper on my mates 355ci small block V8 & so far he is very impressed ! (Grease can sometimes do the same thing as a more permanent gasket sealer without making the removal of the air cleaner such a pain.). All times are GMT-6. Holly offers a very nice Analog-Style Fuel Pressure Gauge that is another option. Even at 0% it's sucking a bunch of air through the IAC port. If the connection is loose it will cause the system to shut fuel off because the signal telling the EFI the motor is turning stops (to prevent excess fuel from being dumped in the motor). (It should be at or near 60 PSI at idle. 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. With the vehicle in neutral, adjust the idle screw until the IAC Position reads between 2 and 10%. By the way, this is a new installation on a 69 Camaro, stock 350, dual sync, etc. When I see that your TPS is 1%, that tells me that you may have an RFI problem. But before you adjust the ECU to lean the idle out, first confirm that your fuel pressure is right. 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. If more info is needed just ask. 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. Is there any chance that your timing has changed since you installed your Sniper? The Street/Strip and race cam setups tend to be too rich initially. When the lambda is 1.0, the displayed AFR is 14.7;1 REGARDLESS OF THE FUEL. 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. Jun 12, 2021. I would start by removing the progressive linkage. Wish I knew about it before I made my purchase. Now it registers zero and I have good idle but it will not register until it hits 60 and up. I would suggest you take a look at that if you haven't already. Also if I give it a Always had to set idle above 950. What can I do? First thing I would check IAC is good 0-5% most of the time. If you have performed the adjustments above and still have RPM issues, it's time to look for clues. Note too that the larger the throttle stab, the more brief the time in that cell and the more gradual the change.Here's what I recommend: Get somewhere where you can repeatedly stop and go. TP range is normal goes up to about 90% with throttle pedal to the floor. The "Gauge Text" is what would be shown on a 2-1/16 gauge or the Avenger handheld display. 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. You're going to have to get this fixed or it's going to cause even more problems than the high idle. Thanks for any info./insight you can provide, Mark. 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. Supports up to 650hp with Four 100 Lb/Hr Injectors! If the TPS reading on your Sniper EFI System does not reset to zero that is a problem that needs to be addressed. Holley EFI Electronic Fuel Pressure GaugeI think its a little ridiculous that I cant see fuel pressure on the display even though its measuring it but whatever. itself out and hold idleeventually stalling. Any suggestions? Sorta similar to a carb having the idle mixture set incorrectly (rich) or the idle speed too low. I've read that a spacer with 4 individual holes will solve this, but after I installed the progressive linkage the noise went away!! That 60% (which is configurable) is known as the Clear Flood TPS. Intake has been on and off 3 times no change. Give that a go and see if you don't make some progress! Hot start it most of the time wont start unless I give it a little throttle. 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. Enjoy! Then, when you experience the high idle, note if the IAC number has increased. 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. You mentioned going from 13.5 to 14.2 but you'd want to go in the other direction--maybe to 13.2. Also when ac kicks on it will idle down and stall. 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. 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. I recently had IAC issues identical to what you describe. I have adjusted many settings and eventually mess it up and go back to the original map. So I had my Idle set up perfect, with idle timing control off and engine hot the IAC was right at 2-4%. If you did not rotate the distributor to set the actual timing to 15 that might be the only issue. If your fuel pressure regulator has failed (and they often fail by blocking return fuel and maxing your fuel pressure) then it could lead to rich idle, particularly until your engine gets up to temp. holley efi. 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. Your suggestion to remove the PCV valve is just for diagnosis purposes, right? This question is really outside both the scope of what we try to discuss in the comments section as well as the overall subject of this article. I also raised idle at Park a bit with the idle screw. When I turn it off and try to restart it just cranks. The tps has slotted holes, can you adjust it to get to zero? Hi I wish I had bought from you but I didn't find this site until now. The symptoms I had was a low cold start idle and going lean coming to a stop. One way is to very carefully watch the handheld monitor, and that may be adequate. The fuel pressure regulator in the Sniper is fairly simple and not prone to failure, as far as I know. If you don't have a working coolant temperature sensor then it will never bring the idle speed down. 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. Make sure that your blanking level is _below_ that (being careful not to find yourself in the situation I describe above.) TPS% = 1 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. I have double checked everythingincluding fuel pressureand have followed the directions to a T.I plan on trying your 10 step process as soon as I get a chance. And yes, monitoring the fuel pressure is the right answer. Car was running great initially. After a stall the car will restart but will be in a high idle. If I read it correctly, the solution from the other thread seemed to fix a constant 300 or so RPM increase. Holley Sniper IAC Surging???? You can manually set it 57 after you run the Wizard if required. The 10 step set up on your page set my idle perfect and iac perfect a very consitant 700. Holley have given a new unit. Running a bbc with coil - my timing is perfect. You will have to do this until the TPS stays at 0% when the throttle is closed. Hello, Chris, thanks for the help.I have not installed the software yet, and I'm having trouble with two cars. Throttle Tip-In puts you in a part of the fuel map where you stay for only milliseconds at a time. 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. One of the great features of Holley's Sniper is the ability to set your air/fuel ratio (AFR) where you want it. One of the signs of a vehicle with a rough idle is a faulty Idle Air Control (IAC) Motor. In the warm state IAC adjusted to a position of 2 to 10%. Have you ever experienced a high idle once the engine reaches 200 degrees?Ive set my idle the way you said and it works great until the engine reaches 200 degrees. The IAC is hanging open and not really at 0. That Ensure that the secondary linkage is completely closed (both visually and manually.). Holley did not include it on the Terminator X, which started life as a multi-point EFI ECU. If you datalog the Sniper ECU and see multiple overlapping traces for the same signal, you likely have RF-induced problems. May God's grace bless you in the Lord Jesus Christ.