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. My issue is that the TP% will not reset with key cycle and its idleing at 9% TP. Genuine Walbro fuel pumps are virtually bullet-proof. Consider adding fuel in the AE vs TPS and/or AE vs MAP ROC tables in the area where the stumble is occuring.Since this is happening at such low TPS levels it is possible that your engine would prefer a lower (richer) target AFR number at idle. Technically it is a warranty-voiding maneuver so proceed at your own risk. Jun 12, 2021. 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. When I turn the key on I can hear it prime, but I don't think im getting enough fuel. 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. They are prone to be inaccurate. It may take a few tries. It's all part of the pleasure of EFI. I used the Casper's Electronics 108103 splitter and carefully soldered my connections. With the engine still idling high park, set the brake, open the hood, and remove the air cleaner. Yes, it will talk to you--but not with words. I took some pics of the sensors page this morning after the car warmed up. What is it supppse to be at idle and while driving under heavy acceleration? Chris's Idle Speed Adjustment Instructions*: *Note: If you are using your Sniper to control ignition timing then I recommend that before you start this process you disable idle spark control If you are trying to do this while the ECU is simultaneously trying to bring your idle under control by adjusting the advance it is going to be counter-productive. Find a lower price anywhere and we'll beat it by 5%! I watched the butterflies start to open at about 35 on TPS. I also noted that after some time, I could change those values as I saw fit. A good example of why it's so important to run a good pre filter in the fuel line. I think that your timing is too retarded. 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. 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. Then, when you experience the high idle, note if the IAC number has increased. (Plus they it just looks way cool in your engine compartment!) 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. Ilike a few othersam having idle issues. If you datalog the Sniper ECU and see multiple overlapping traces for the same signal, you likely have RF-induced problems. I recommend you have a look:https://www.efisystempro.com/efi-pro-hangout/holley-sniper-efi-instruction/solving-sniper-rfi-problems, I recently purchased your fixed linkage to open primaries first and the throttle linkage extender to also get a smoother pedal. We will definitely be sticking with Holley from here on out for future retro-fits. Thanks again. I asked him a million questions and waited a long time to save up before purchasing the system and I have asked a lot of questions throughout the installation process. I am Japanese who attached Sniper EFI. If I go any more it will ping. The RPM would increase for no reason. carburetor setup, but it does blow when I can't jump on the highway like I use If you did not rotate the distributor to set the actual timing to 15 that might be the only issue. It only comes back to normal if I turn the engine off and on again. That initial rev is going to be determined by your IAC Park Position. Really appreciate the amount of learning im getting off here. First, I'm kind of insistent about not changing any of the default settings unless the vehicle absolutely will not cooperate enough to drive/learn, and only then if you have a specific understanding of the problem and a specific solution. There are two ways to address this--you can let the system learn or you can manually adjust the acceleration enrichment. 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. Shutoff engine wait 30 seconds, turn key wait for display to come up, start engine. In the warm state IAC adjusted to a position of 2 to 10%. Again, I would lean on that solution to let the vehicle drive/learn before you try to "fix" anything. One of them might be faulty. Try it! Two months fighting, cursing, not getting any help from Holley OR the forum, and a stupid little tin plate. It's hard to know what the previous owner did right versus wrong. 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. Even then, recognize that over time the IAC will need to be readjusted to compensate for minor changes that will cause it to drift. It wont fire up. Sometimes it sounds like it wants to crank at the start but runs out of gas. Switch power to the Sniper on and crank the engine. I have one customer who is having some similar issues and his AFR is down at 9.6:1 when it won't start. It turns out that some of the Snipers are shipping with the minus 40-degree setting drastically lower, as shown in the following image. If it creates an issue (not normally the case) then you'll know. Even at 0% it's sucking a bunch of air through the IAC port. 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. It won't take much! Drive great and idles perfect at stop signs. A simple remove & clean will remedy this . I appreciate everything you are saying. I keep doing that with the same result. If I were there in person I would test the function of the IAC (see this article.) At some point you come upon problems that evade the easy answers and this is a good example. 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. The distributor was loose. EFI System Pro had everything I needed for my EFI upgrade. It then idles up from 750 to 1100. All times are GMT-6. Also ensure the TPS Position returns to zero at idle, & the IAC Hold Position isn't setup too high. The warmer the motor, the higher the idle will be at this point. We've already tried adjusting the Acceleration Enrichment chart in all ways, going up and down, RoC Blanking, everything, it has no effect. hard start about 1/2 throttle from stop it bogs down after 3 or 4 seconds.What I So check that timing and I think that you're going to find you need a good bit of advance. I think that the more important point is that Holley kept sending him units until everything was working. Fortunately, I have an article that goes into this in some detail. Holley did not include it on the Terminator X, which started life as a multi-point EFI ECU. And, hopefully, within those degrees you will find a place where you don't get the whistle. The throttle position should be zero. Now, 1% on the TPS isn't a problem, but when it goes to 2% (which is inevitable if you have RFI moving it to 1%) then the IAC is going to go to it's hold position (30% by default) and the engine is going to rev up. It appears that I could now use the dongle and a laptop to custom tune for idle issues if needed. I'd say make sure you buy from someone who can give you good after-purchase help (hint!) 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. 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. Hey Chris So I have been driving it for about 400 miles now to numerous car shows and going out for cruises around town, trying to work some of the bugs out from everything we did this winter, but I notice when I take off from a stop sign or I cruise at a very low speed (say30 mph) it seems to be very boggy from no throttle to about 1/8th throttle. When you experience this, before you touch anything or shut the engine down, first look at your TPS and your IAC. 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. It's not necessary to drive it that way. :-). Some have suggested mis-setting sets the idle speed at 850 RPM but I suspect it is not a fixed number but rather a delta of about 300 RPM above the target. 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%. 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. Chris, Then it will ramp down to 1200 but will not return to idle. I would disregard any correlation between idle control between the Stock and Street/Strip setups. 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. You can find those settings here: Handheld: Tuning > Advanced > Advanced Idle > Rampdown, Software: Idle > IAC Settings > IAC Ramp Down. Do I need to try taping up the IAC port and setting the idle off the idle screw? A couple of those and you should feel it getting better. :-) Just don't let the parts go flying. the gas it catches itself and runs fine at slower speeds. I put it in neutral and the idle RPM had increased to 2100-2200. I think you will find that it will learn its way through this. Ultimately, it is about making the pedal softer, particularly at initial throttle opening. Then you can take a close look at the IAC and see if it is opening. ChrisI finally got everything resolved. 34K views 1 year ago Holley Sniper How to Set The IAC Idle air Control in 5 minutes or less. It started right up and we did your idle control fix and all is good at idle. Supports up to 650hp with Four 100 Lb/Hr Injectors! 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 There are a few tell-tale signs that can help you diagnose the problem. Give us a hand! Rpm with 4-8 iac but it still shows red and shuts off randomly at idle and it won't even drive 2 miles without shutting off. When you first posted this I had no idea how to respond. It sounds a little different from mine, since it commands a 1300 or so increase intermittently. Was perfect idle iac reading 3. Seems like its too slow to grab idle when ac kicks on. Wish I knew about it before I made my purchase. Hopefully replacing the pump again will resolve both issuesWhoa. To start viewing messages, select the forum that you want to visit from the selection below. This curve runs fom -40 degrees to 260 degrees, and gradually reduces the RPM along that range. Then Friday night as I was driving home, the car started acting up. I'd suggest that you assume everything the previous owner did was wrong until you can prove that it was done correctly. Please check your process again and see if you can see very specifically what is not working correctly. Am I missing something. I would suggest you take a look at that if you haven't already. No problems with either cold or hot starts. It is reliant on the data acquired by the included wideband oxygen sensor. Your task will be to find that. Drop the IAC parked position a bit at each temperature point and sort of back into the solution. )Since this isn't a consistent issue with all Snipers that tells me that different IAC settings tend to make the whistle. I will confirm TDC with balancer but I have had balancer off and timed it before and after with same results. Thanks for the information you have provided on this site. See these. But if I take off from a stop and go to 1/4 or 1/2 throttle its fine and takes off like a banshee. If you hit the gas it pops & backfires through the throttle body. 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. He thought that something was wrong because when he set the idle 50 RPM below his target the resulting IAC postion was far too big. To get it to idle the tps is at 2-3-4% even with linkage disconnected and a return spring installed. The engine makes very low vacuum at idle. Idle quality is great, RPM is good, sometimes IAC is now between 2 and 5 exactly where it should be. We can not hit it at all, we hit the pedal abruptly, the engine gives a lot of excess fuel, the AFR gets super poor at first, the car stops, then the AFR gets super rich and the car runs until it cleans up. Intake has been on and off 3 times no change. No power at the programmer and no fuel pump running. Should it not do the opposite and do this on a cold start not warm. If I try and get the 2-10% i get all the way up to 1200 rpm. 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. 1. Capability Range: Moderate If you use your handheld to go here: It shuts off when coming to a stop sign, at any cruising speed and romdomly at idle in park but never when excelerating. But there are several degrees of play there in which it should still work fine. Sorta similar to a carb having the idle mixture set incorrectly (rich) or the idle speed too low. % = 49 Adding a wrap to the return spring on the shaft is one alternative to solving this. 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. :-). If I read it correctly, the solution from the other thread seemed to fix a constant 300 or so RPM increase. An undersized or partially plugged fuel filter is a classic EFI installation mistake. Thanks for sharing that, Jason--great info! EFI parts, including the throttle body, and the problem persists.Please give me a hand. 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. technical rep said "You ahve high fuel pressure". (Grease can sometimes do the same thing as a more permanent gasket sealer without making the removal of the air cleaner such a pain.). ?I never had my Carb Cold start RPM any higher then 1600 RPM.THANK YOU. Next, reach down into the secondaries and push the butterflies closed. 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. We are using Target AFR of 9.0: 1, Fuel Base approximately 40% higher. I have installed my Sniper and the car runs great. The Tech Tips and discussions are also great! I pulled over and turned the car off and then back on. What can I do? Yes it is controlling the timing and I had issues at first and it controlled the idle just fine. :-)Yes, learn impacts idle too, and remember the even when the basic learning is done there will continue to be some learning for changes in weather, altitude, etc.Go ahead and try a few idle settings and see how they impact the idle-speed searching. 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. Thanks again for your insights! Comp. So you installed your Holley Sniper. I am right back to where I started. 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. Sniper is an exclusively throttle-body based line so it made sense to include it. The tps has slotted holes, can you adjust it to get to zero? You're going to have to clean up the wiring in your engine compartment, In particular, look for spark plug wires that might be running near your throttle position sensor. If idle drops below 800 it wont come back itll chug around 300 rpm for a few seconds then die. Pricing was reasonable, shipping was prompt and Chris helped me with a wiring question during my install. This is normally used as an A/C idle-up circuit. It's a Chevy 350 bored .030" over it has a cam in it what I was told is the cam has the firing order swapped. Hi. Thanks, That is an strange situation. Even 50 RPM can make a difference in how much impact the transition to Drive has on the idling engine's ability to stay at a fixed RPM.I would not recommend it in this situation but anytime a "kick" in idle speed is desired that is easily done by setting the kick value in Tuning > Advanced > Adv. There is no sense proceeding until your TPS is at zero at key-on. After doing TPS reset it starts fine but when you give it some gas it hangs at 1500 and will not return to idle. 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. The first thing I'd do is check your fuel pressure with a gauge like this. I am at the point where I almost insist that every Sniper EFI System owner purchase one of these. Let https://www.youtube.com/watch?v=2JpHlS1ymBc, If this is your first visit, be sure to I have verified that there are no vacuum leaks, not to mention the car runs to good to have a vacuum leak bad enough to make this noise. I recently install a sniper efi. Ensure that the secondary linkage is completely closed (both visually and manually.). engine works beautiful, the car runs a lot, but suddenly, the engine does that. So, this is what it takes to put a Sniper on a small-block Ford. Your second problem should be a bit more concerning. Have you confirmed your fuel pressure at idle is 60 PSI? As always, I recommend great restraint in changing any of the parameters until a significant amount of learning has taken place. 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.

My Husband Resents My Chronic Illness, Lady Helen Taylor Husband, Binding Of Isaac Item Id, Tungsten Lewis Dot Structure, Articles H