holley sniper efi iac problemsshallow wicker basket
I'm going to jump out on a limb here and say you either don't have adequate fuel flow or pressure. By the way, this is a new installation on a 69 Camaro, stock 350, dual sync, etc. Realize that when you drop the throttle, the engine enters a condition it will only see for a fraction of a second at a time. I watched the butterflies start to open at about 35 on TPS. There's still a very small amount of airflow that squeezes past a closed IAC valve; it's that venturi like sound you're hearing. I can have it working fine (5% to 10% at target idle at operating temp.) If I read it correctly, the solution from the other thread seemed to fix a constant 300 or so RPM increase. After only running for about 15 minutes or so the system starts to fail stalling the motor. I enalble the idle timing control and fired it back up Iac was at 32% but it would come back down after a bit to around 26%. But when you have it then you can look for exactly what the IAC is doing at that point, and if there is anything that might lead to this happening. On a cold start it will idle at 750 everytime, But if its hot start it will jump upto 1600rpm for 2 seconds then come back to 750. These are "transitional" cells, and you really have to make the effort to learn in these areas of the map. When I first told him to check for leaks he looked back there and said "all good". 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. If this is the case then some adjustment of the linkage or the butterfly plates themselves is necessary. I haven't driven it for the 30-40 minutes like the several times it idled at 2200. IAC looks good once it finally s fires. Then Friday night as I was driving home, the car started acting up. I' m going to put the 3rd new pump this coming friday. Or alternator? 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. A good example of why it's so important to run a good pre filter in the fuel line. Sorta similar to a carb having the idle mixture set incorrectly (rich) or the idle speed too low. I will be at a red light trying to brake against the engine. If I rev the engine a couple times in neutral it will finally return to idle & usually will not do it again for the rest of my trip. 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 I ask because I'm using a PCV valve with my Sniper and have random idle issues as well. It is always best to get the base map as close as possible before adding acceleration enrichment. 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%. 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. When the idle speed screw is turned all the way out there should be just enough room between the bore and the blade to catch your fingernail. If the screen shows iac at 0 and you block the hole to find it open what does that mean? I recently detached the TP sensor from the side of the sniper to physically move it and it still would struggle to get to 0%. Um, no. However, whenever you start changing things, you can get into a chain reaction. This value is itself enough to raise the idle a bit. One way is to very carefully watch the handheld monitor, and that may be adequate. 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. Take it a step at a time. Let me be perfectly clear: If your engine will not drop below 1350 RPM with the idle speed screw turned all the way out then you have an air leak. You are aware of the idle-up problem. 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. I had a customer who struggled to understand that. We have shipped quite a few of these to customers in Australia and New Zealand so I know that there is becoming a good following there!We recommend this Inline 10-micron fuel filter to prevent problems like that. What might cause the TPS to go to 2%? Interesting question. Hi. I don't want to go on too long here but once you know if you're trying to add or remove fuel, there are a couple of ways to go. Running a bbc with coil - my timing is perfect. Yes it is controlling the timing and I had issues at first and it controlled the idle just fine. Now that you've installed at least four Snipers it is going to be imperative that you learn to create and read datalogs. I have a 406SBC that does most everything right with this sniper setup. No big deal, just time to re-adjust! First--besides the fact that it's not represented on the display, it is not even a parameter that you can datalog. 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. 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. It's all part of the pleasure of EFI. Price Point: $, Advanced throttle body injection systems capable of transmission control and more. May God's grace bless you in the Lord Jesus Christ. We offer some tips to help with that. Turning off and then on again, the engine returns to normal. Then it changes and will not idle down, the handheld will display 0% IAC but you can see and feel that the IAC valve is more like 100%. Even at 0% it's sucking a bunch of air through the IAC port. Find a lower price anywhere and we'll beat it by 5%! I pulled over and turned the car off and then back on. The IAC going to 30 is normal. I recently had IAC issues identical to what you describe. Everything was working perfectly and I shut off the engine. 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). At 0% it shouldn't be sucking any air through that port, correct? I readjusted my IAC, now it's perfect. 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 used the Casper's Electronics 108103 splitter and carefully soldered my connections. Then do it just a bit faster--just enough for it to bog a bit. Definitely not 90. Short drives is fine then it'll I started with right after I first adjusted for 2% IAC and took pics about every 30 seconds over about 2 minutes. I'm happy to walk you through what is required. (Plus they it just looks way cool in your engine compartment!) Could be a bad IAC motor, replace it and see if that solves the problem. I set the AFR at 13.5 and all is good now. Sniper EFI Idle Tuning. :-). Enjoy! Well, it turns out that with the current firmware this throws the IAC control into a bit of confusion. check out the. If you drop it too far the engine will stumble or stall when coming off the throttle with the car out of gear, so you'll know when you've gone too far. The problem I'm having is I cant get the IAC to drop down off 100%. But before you adjust the ECU to lean the idle out, first confirm that your fuel pressure is right. That's not the IAC Hold Position, it's a percentage value. What I can't explain is why your TPS is acting so randomly. Start with the most gradual throttle input you need to launch well, then slightly increase until you feel some stumble. It didnt do this with the carb on it. Ive played with the timing on this thing multiple times.Car was fullly restored last year. I would suggest you take a look at that if you haven't already. Also if I give it a If you use your handheld to go here: Definitely would have went with you guys. It will learn the fueling eventually either way, it's just that one might get you there a little faster.If the idle is fine at start-up but then increases after you depress the throttle then you might need to lower your IAC Hold Position a bit. Shutoff engine wait 30 seconds, turn key wait for display to come up, start engine. Do you have any clue? You can adjust this number up or down but there is really no need to change it unless the car is stalling.The sucking sound is just what happens when the Sniper EFI System is paired with certain intake manifolds. (If you do this you will need to reset the -40 degree setting mentioned at the top of this article. 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 Advanced throttle body injection systems capable of transmission control and more. Or, at least, it should. In your case, however, I think you're close to getting it running. This happens no matter how much I adjust the idle screw. You just need to go back through the IAC adjustment procedure now that idle timing control is enabled. When I finished the install on my C10, I set it as follows: 13.1 at idle, 14.2 at cruise, and 12.9 at WOT. I'm compltely stumped and my wife is certainly upset I'm spending so much time between the garage and the computer for something that should basically run out of the box. 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. You've got it running and warmed up but now you need to set. That is the first thing you must find. Thanks. 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. Since the shield was put on, not a single problem, not one. Honestly, I've never seen this happen but if the butterflies were misaligned on the shafts it could allow too much air to enter. 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. But they are 100% committed to your satisfaction. When I covered the IAC with my finger, the RPM dropped so low it stalled. mail today. Perfectif you have the original synchronous linkage. Fortunately, these are much easier to solve. When this occurs, I sometimes can shut it down and it will return to the correct settiings. Great work, expert! 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. Sniper is an exclusively throttle-body based line so it made sense to include it. By the time I was near home, the idle in Park was 1050, IAC 0. Since a key cycle resets it to 0 and out to 30 or wherever Since that has long been corrected we have moved that information to the bottom of the article.). 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. Any ideas here? That's a nice change of pace--a low idle issue! 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. Don't try to correct for the fuel. Can the return line be an issue?So far this sounds like an ideal setup.>I have had 2 faulty gpa-4 255 walbro pumps go bad. is train the system or there is actually something wrong.I do love the system at 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. I've made all the adjustments, all the settings, and the IAC issue is driving me crazy. I have an entire article on choosing between Sniper and Terminator X throttle body solutions and while Sniper is still a sound choice for some applications, Terminator X (with transmission control) is hands-down the way to go for those who need that. Thanks for the info Chris. Cycle the ignition as instructed by the handheld and then navigate to the distributor setup screen. I have seen this become blocked with debris / dirt in the fuel system and cause a high fuel pressure condition . Car was running great initially. 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. Hello, I am having a tps and idle issue. (Do this while you are cranking.) IAC Pos.% = 0 I think I figured some of my problems outI'll try to explain. 90% of problems, (INCLUDING MYSELF) could be answered/fixed by just reading the instructions. I then saw you guys have an awesome little gauge that can hookup inline to the snipers existing fuel feed?? Duty Cycle% = 3 Ok, so there are a couple peculiar things going on here. I have never seen issue when CTS is below 120 degrees. 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. When I am coming to a stop, the rpms will hang at 1200-1500 rpms. When you have the issue you should disconnect all hoses and plug the ports on the Sniper. That disappears as soon as the throttle is pressed and then you immediately revert to your timing table.You can certainly use the compressor to initate the IAC Kick, but remember that this is just a temporary idle boost to ensure that the engine doesn't die when the AC is first turned on. These problems will go away when you do that. Maybe give it a half-turn before you start it and then start and tweak. It's not that they (or any other manufacturer) is 100% perfect. In the Wizard, select the stock cam setting. It might be necessary to insulate or re-route your fuel lines if this can't be solved any other way. Yes, it will talk to you--but not with words. But I am having troubles.When stepping on the accelerator slightly with idling, it will be 2000 RPM all the time. If the TPS is 1% or below then the air is coming from somewhere else. 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. 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. Target AFR at idle is 13.8%. The noise changes sound with the throttle position. The fix? To keep it running in gear, I have to bump the neutral idle up just over 1000 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. You can disable the idle spark control at the locations below. Not to bandstand here but this is the point when where you bought your system is so important. But he kept having problems so eventually he did a complete check and then he found the problem. 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. That is the IAC hold position. This only happens when coming to a stop and the idle is ramping down to the set idle RPM. When I start the motor I have to push on the accelerator pedal for the motor to start. Those don't impact the way the engine runs and can cause the whistle sound you describe. And since they really had an insanely-tight monetary and real estate budget in the Sniper EFI System, it is unlikely that the added something that wasn't absolutely necessary--and then forgot to use it..And you are spot on about the little Earl's gauge with optional -6 AN port. 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! So this is my issue ( I did just email Holly). This minimizes installation time and packages really well on a diverse group of engine applications. Thanks so much for reading! Now I have most of the bugs worked out it runs fine on the highway and around town it's just the idle. Ultimately, it is about making the pedal softer, particularly at initial throttle opening. I've not heard of any others with this exact issue so I don't think it is a common problem. Fortunately, Holley has another product that can solve that: Hydramat.. Hydramat is not inexpensive but you won't believe what it can do. You want to ensure that nothing is hung up in there.The only thing that I can think of that would cause the fuel pressure to spike when the motor starts is the increased fuel flow at the higher alternator voltage (jumping from 12.0 to 13.5 volts or so.) itself out and hold idleeventually stalling. 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. 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. Copyright 2022 Holley Performance Products, Inc. All right reserved. If you hit the gas it pops & backfires through the throttle body. Pw. If I read it correctly, the solution from the other thread seemed to fix a constant 300 or so RPM increase. I have a Holley Sniper for almost 11 month now and it was running fine with no problems until now. Capability Range: Advanced If you complete the process and find that the IAC is less than 2% at idle, repeat the process and use the set screw to make the RPM about 60 RPM below the target. 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. Now that you've got your IAC set I'm going to recommend that you run your setup wizard again, which will reset the ECU to the default settings. My primary reason for going EFI was drive-ability, (Startup and take off without waiting for the engine to warm up) and not have the occasional hesitation a carburetor has especially just barely opening the secondaries. So you installed your Holley Sniper. 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. Follow this link to download it for free if you have not already done so. When the secondary throttle blades are centered in their bores and pivot freely, an additional return spring is not necessary. Throttle body mounted ECU - no extra boxes to mount. I have driven a stand-alone transmission controller for the 4L60E in my (then) Sniper-equipped '95 GMC pickup using the Sniper TPS with complete success. If you feel you have no other choice but to run a Sniper and stand-alone controller then you can give this a try. Also its extremely rich at idle. is the fuel pressure. 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. In the time it takes to add your email address you can be at the top of the heap for getting the latest information from our authority. Resistance results in heat and heat results in more resistance. That could be a problem with the TPS or it could be some sort of throttle linkage issue. When I turn the key on I can hear it prime, but I don't think im getting enough fuel. If it is already adding fuel, it may be worth expanding this into the area where the tip-in is occuring (and where there is no learning occuring. The 10 step set up on your page set my idle perfect and iac perfect a very consitant 700. If the engine will after the 4 seconds that the IAC kick drops off then it's not really going to help.At any rate, it costs you nothing to advance the ignition and see if that doesn't improve the idle, right? (Grease can sometimes do the same thing as a more permanent gasket sealer without making the removal of the air cleaner such a pain.). Should it not do the opposite and do this on a cold start not warm. And your question is very perceptive: You must first know whether the bog is a lean or a rich condition before you can make the correct adjustments. There is no real mystery here. As always, I recommend great restraint in changing any of the parameters until a significant amount of learning has taken place. :-DStill, I hate to leave someone hanging so I'll try to help. Hey Chris! By the way your site and your accessory products are nice. If I adjust idle screw out to get the tps to zero or even 1% the engine will not idle. The manifold pressure increases with the throttle opening but the RPMs are still low. Hi Chris, I have a lean stumble on throttle tip in 2-3% tps taking off from a stop light the afr will go to 19afr and the engine will stumble for a split second. 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 There are two ways to address this--you can let the system learn or you can manually adjust the acceleration enrichment. It sounds a little different from mine, since it commands a 1300 or so increase intermittently. Fuel Flow lb / h = 12.1 Though it started and ran good, it was dumping fuel and would not lean out to AFR set points. However based on your reply I connected the Fuel Pressure gauge and The warmer the motor, the higher the idle will be at this point. Hello Chris. But, if the idle is so high that it is making you crazy then you might try dropping that number just a bit. I did buy the Sniper from you guys and the service was fantastic. It's the same one that Holley puts in their Sniper Master Kits and I've never heard anyone with anything but good things to say about it. It could be a problem with the power/ground for the Sniper but much more commonly this is a result of too much RFI. 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. A common issue we see is a result of poor fuel pump grounding running a eyelet from the pump ground to a rusty or painted surface. Your task will be to find that. Your AFR is pegged lean. Stupid question, but where do I see if it's entering Learn mode? Check the Distributor Tach Connection to the EFI. Covered the IAC port and set idle for 850 ish. 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. check, I guess after reading everyone saying how great the system is after EFI Systems based on Holley's world-class Dominator and HP ECU's. And increasing your idle via the idle screw was also a good idea, because that will lower your amount of IAC that is necessary to keep your engine at the target idle speed. There's a procedure there I can share with you if you'd like.. This can cause the engine to run rough and may even lead to engine damage. When I covered the IAC with my finger, the RPM dropped so low it stalled. Target AFR, A / F = 13.5 When you open your IAC to 30% you are naturally going to have a high idle condition. I also tried changing roc/map to 8 from 15 again no change at all.My ve table is smooth and tuned I even changed my AFR to 13.5 from 14.2 and no change at all. 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. Reply Quote. They always responded to my questions with guidance that helped me choose the right system for me. The on board fuel pressure regulator in the Sniper throttle body has a small filter clipped over one end . NOTE: Do not attempt to set the target idle speed and IAC position until the engine is above 160F! Price Point: $$, EFI Systems based on Holley's world-class Dominator and HP ECU's. Next, reach down into the secondaries and push the butterflies closed. I am having an issue with the IAC on the Sniper. This page was generated at 12:26 AM. I was looking at a data log from my truck earlier this week and noted that at idle my IAC was zero. If the ECU has not spent some significant time learning yet, I'd recommend going back through the setup wizard and getting everything back to default. Once engine is warmed up been driving for awhile. Once you know that then you can work on those problems. One of the great features of Holley's Sniper is the ability to set your air/fuel ratio (AFR) where you want it. 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. close to idle with the IAC between 2% & 12%. So glad this was helpful. I've read that a spacer with 4 individual holes will solve this, but after I installed the progressive linkage the noise went away!! When you experience this, before you touch anything or shut the engine down, first look at your TPS and your IAC. I believe that for the HyperSpark the Reference Angle should be 57.5. Please help. The team at EFI pro are some of the best I have ever dealt with when coming to ordering parts or having the knowledge to answer any question you may have. Copyright 2022 Holley Performance Products, Inc. All right reserved. Holly offers a very nice Analog-Style Fuel Pressure Gauge that is another option. 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. Jump on board now! Hey Tommy, we've got at least one thing in common. That initial rev is going to be determined by your IAC Park Position. Worst case you'll have a spare on hand, and if the TPS is faulty you will have solved the mystery. I followed the instructions and set the IAC to 2-9% when warm with idle at 850 RPM. Confirm the placement of all wiring, ensure that the WBO2 sensor is positioned properly, etc. All of the wiring exits below the rear fuel injector cover, for a completely stealth installation. Since your target is probably more like 700, and since 2400 is way over 1700 RPM, it's going to leave the IAC in the park position.Buckle down and find how air is getting into your engine. I've been messing around for a bit trying to eliminate any possible vacuum leaks. Ive also used another snap on light to confirm. You are looking in the right area but I would probably not change the ROC blanking. I had that problem, right out of the box it would not power up, sent it back in, had defective hand held. 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. Without it you are working in the dark. Any idea's? Capability Range: Advanced I followed the instructions and set the IAC to 2-9% when warm with idle at 850 RPM. I took some pics of the sensors page this morning after the car warmed up. Once it commands that high idle I haven't found anything to return it to normal, other than shutting it down and restarting. Again, I would lean on that solution to let the vehicle drive/learn before you try to "fix" anything. Often, folks will say, "I did everything you said. 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. I have a Holley Sniper EFI with HyperSpark ignition. 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. I put it in neutral and the idle RPM had increased to 2100-2200. The link above includes the option to buy a -6 AN It then started working normally again. He has walked me through every question Iv. I.e. 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. Were the additional load a simple step function it would be challenge enough for the ECU to gracefully increase the engine speed without overshooting. EFI parts, including the throttle body, and the problem persists.Please give me a hand. The small rubber plug had a leak. Laptop Access At some point you come upon problems that evade the easy answers and this is a good example.