I figured out I was going the wrong direction when I was messing with the AFR programming. 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. Definitely not 90. Not that I noticed. When I turn it off and try to restart it just cranks. I have a set of 8.8 Accel Rfi suppression wires on it. Once engine is warmed up been driving for awhile. I will turn it up some more.Is this something that the ECU will learn? Since that has long been corrected we have moved that information to the bottom of the article.). Really appreciate the amount of learning im getting off here. I did buy the Sniper from you guys and the service was fantastic. 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. It will still change a bit with weather changes and when you get into infrequently-used sections of the map, but it's nothing to worry about.Regarding your idle speed immediately after start-up, that is determined by your Idle Parked Position. Based on your situation above as well as some of other experiences, I recognized that I needed to improve my tuning procedures above to better explain what steps to take if that 10-step process doesn't completely solve the problem. If I put the truck in park it comes down to idle. Thank you for your input. Um, no. Thanks. 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. Covered the IAC port and set idle for 850 ish. First, recognize that the IAC and the TPS are not inter-related in any way. Second, Holley just released over the weekend a video on how to implement a flex fuel sensor on their HP and Dominator ECU's. % = 49 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. I've tried repeatedly re-creating the scenario in hopes that the E.C.M. The jack-rabbit start can usually be minimized by adjusting the throttle linkage. If the engine idles at 750 RPM with the throttle plates all the way closed and the IAC at zero then there is some sort of an issue. To do this, open up the Initial Startup gauge screen that was used in section 17.0. 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. Earl's Mechanical Fuel Pressure GaugeI could use that for a quick troubleshooting for 1/3rd the cost of the Holley one. I tried adjusting my IAC up to 10deg in both directions with no change. With select intake manifolds, the distributor housing and IAC valve on the back of the Sniper EFI throttle body are fighting for the same . The 10 step set up on your page set my idle perfect and iac perfect a very consitant 700. The problem I believe this is creating is after I start vehicle (and its still in park), the IAC drops down to my hold percentage of 10% (since throttle % is not 0) before engine is warm and therefore causing the engine to stall out. Don't try to correct for the fuel. If the TPS is 1% or below then the air is coming from somewhere else. I've been messing around for a bit trying to eliminate any possible vacuum leaks. If this is the case then some adjustment of the linkage or the butterfly plates themselves is necessary. Sometimes it sounds like it wants to crank at the start but runs out of gas. He has walked me through every question Iv. hard start about 1/2 throttle from stop it bogs down after 3 or 4 seconds.What I 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. So, this is what it takes to put a Sniper on a small-block Ford. Next, clean the IAC and all related parts with brake cleaner. It's pretty hard to get the header tubes glowing at idle with a lean AFR. applies here because it is so important to realize that just because the IAC The headache is the Acceleration Enrichment. When I cover it with my hands, it gets quieter. If I block off the iac with tape , I can get it to somewhat idle, but its not consistent. The distributor was loose. Jun 12, 2021. Any idea's? It's not that they (or any other manufacturer) is 100% perfect. 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. Look over all of your vacuum lines and fittings. Is there away to lean the idle out? Ok, so there are a couple peculiar things going on here. Could the IAC be broken/malfunctioning? The Sniper EFI Manal says not to but many EFI installers have informed me that the transmission only reads the 5V TPS signal from the Sniper EFI & does not draw any power so will not affect the Sniper EFI TPS output. Holley have given a new unit. So glad this was helpful. I will be at a red light trying to brake against the engine. If I put the truck in neutral the TPMS will raise all the way up over 2000. 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. I'm Having trouble with the Sniper on high Idle. Took it for a lap around the block and came back. Or alternator? 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. So if you are trying to achieve a stoichiometric mixture in ethanol (which is achieved at an AFR of 9.0:1) then you should continue to target 14.7:1 since that is what will be displayed. Yes, the sound coming out of your Sniper throttle body is a pulsation from the fuel pump that is pulsing the mechanical fuel pressure regulator. I've been having problems with my sniper efi just shutting off. Overview. If so remove it. I did all of this before seeing the link you sent. 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. Installed sniper on 65 galaxie. You can manually set it 57 after you run the Wizard if required. However, I can't think of a single one that was because of low vacuum. Usually it wont stay on 0% very long and soon changes to another number like 1 or 2%. check out the. All times are GMT-6. NOTE: Do not attempt to set the target idle speed and IAC position until the engine is above 160F! Properly configured, the Sniper does a fantastic job of responding to the transition from Park to Drive. The broad consensus has been that the Sniper is an amazingly straight-forward install and starts and tunes as expected. I think you will find that it will learn its way through this. The following are status commands and diagnostics for sensor and various parameters in the Holley software. Hey Chris, I installed a Holley sniper on a small block 400, first start was great! Mechanical Fuel Pressure Gauge on the inlet of your Sniper, now is the time. I recently install a sniper efi. you have it set. Copyright 2022 Holley Performance Products, Inc. All right reserved. Note that Brazilian gasoline has 27% ethyl alcohol. When I turn the key on I can hear it prime, but I don't think im getting enough fuel. When I covered the IAC with my finger, the RPM dropped so low it stalled. Also what would you say a desired idle should be for a 3 speed automatic ford? :-DStill, I hate to leave someone hanging so I'll try to help. By the way your site and your accessory products are nice. 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. After much diagnosis, I ended up replacing the intake manifold gaskets. Don't be surprised if one or the other is slightly open. Idle quality is great, RPM is good, sometimes IAC is now between 2 and 5 exactly where it should be. 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 will turn it up some. Thanks for all your help Chris! Hello Chris. I installed a Holley Sniper on my Ford Maverick 302 V8. Coming home from work today it was much warmer and took a little longer due to traffic. I recently had IAC issues identical to what you describe. I' m going to put the 3 rd new pump this coming friday. By going into the IAC settings and turning off the Idle Spark control and setting Target Idle to 750 RPM my idle issues are gone, and it now returns to desired idle after cruise. It's hard to know what the previous owner did right versus wrong. I'm running a 408 sbc. Holley will take a look and tell you you have RFI and wish you good luck in finding it. Have you confirmed your fuel pressure at idle is 60 PSI? Its on a big block Mopar with stock electronic ignition . Have you checked your fuel filter and made sure it's not plugged?If both of these are okay you're going to have to find a way to monitor your fuel pressure while under load. Idle Tuning is a very important part of tuning any EFI system, especially our self-learning units like Sniper or Terminator X EFI. (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'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. That is not the way to go. Since it is unlikely that anything else changed it is most likely the IAC is problematic or the butterflies are not shut all the way. 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. You might have a bad O2 sensor, really bad exhaust leak or a problem with the ECU. To figure this out it's going to be important to gather a bit more data. As always, I recommend great restraint in changing any of the parameters until a significant amount of learning has taken place. Do you have a PCV on the engine? The AFR was pretty consistent around 13. It starts cold fine, its just when its hot. Fortunately, I have an article that goes into this in some detail. 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). You've got it running and warmed up but now you need to set. A problem since day 1 - YouTube Leave a comment if you've had this issue and how you resolved. I readjusted my IAC, now it's perfect. Closed Loop Compensation rises to 100%, Do I just keep pushing it the same way to If you suspect this then try to find a situation where this occurs where you can safely check the secondary throttle shaft and see if i's slightly open. 1. is the fuel pressure. Why is this? If you go too high then the motor will not return to your target idle when you come off the throttle. Maybe give it a half-turn before you start it and then start and tweak. While you have over 200 miles on the system, you must realize that in the part of the map where the ECU finds itself during lanches you might only have a total of 5-10 seconds in any given cell. Should it not do the opposite and do this on a cold start not warm. In the context of the Sniper the AFR that is being displayed is the AFR of ethanol-free gasoline based on the lambda that is being read by the AFR. Use the idle speed screw to set the idle at a comfortable warm-up speed. Thanks Again for your help. The person I bought it from said he never could get it to run for more than a few seconds. What is it supppse to be at idle and while driving under heavy acceleration? I would suggest at that point you need to contact whoever is providing your tech support and find out why the default values are not working for you. Cheers Darren. Start with the most gradual throttle input you need to launch well, then slightly increase until you feel some stumble. Engine has never stalled with Sniper system, once placed in Drive it just goes!!! Thanks for your very detailed question! RPM = 1200My slow gear I leave with 650 RPM, the IAC Position I leave between 5 and 6%, the We will definitely be sticking with Holley from here on out for future retro-fits. The throttle position should be zero. Everything was working perfectly and I shut off the engine. I notice at 2-3% tps the iac is 18-25% and it stumbles, when the iac gets to my hold position of 30 it stops. When I am coming to a stop, the rpms will hang at 1200-1500 rpms. Physially manipulating the linkage by hand will generally reveal if you have a sticking linkage that is preventing the TPS from returning from zero. Generally, one of two things: a stuck throttle or noise on the TPS signal. They are prone to be inaccurate. Capability Range: Moderate 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. 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 right back to where I started. One of the most common symptoms of a Holley Sniper EFI problem is an air/fuel mixture that's too rich or too lean. 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. Unless you have ignition control enabled, that is the only thing it can do to reduce the idle.Realize the only things that can cause the car to idle up as you describe are air and ignition advance. It wont fire up. 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. When I drive with warm engine the IAC is at 30% when pushing gas, but shouldn't it be at 0%? 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 keep doing that with the same result. TPS 0. Let's start by not assuming anything. Car has run perfect every time and has never hesitated or stalled since. Another suggestion is to add an extra turn to the spring built into the linkage to increase the closing force on the throttle shaft. mean that the IAC is causing it. 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? The noise is definitely coming OUT of the throttle body. Good The only other thing I changed was accel enrich but whatever way I go doesn't seem to change anything unless I change it drastically. So check that timing and I think that you're going to find you need a good bit of advance. Any suggestions? I would only play with this if you are finding that the other adjustments I suggested aren't working. Glad to hear that things are working well! We're having trouble with a Ford Maverick 302 V8, using ethanol. check out the. The engine has 14: 1 compression ratio, we can not use gasoline. I followed the instructions and set the IAC to 2-9% when warm with idle at 850 RPM. By the way, this is a new installation on a 69 Camaro, stock 350, dual sync, etc. I have an entirely separate article on Solving RF Intereference Issues. At this time, TPS is 0%, IAC is 50 to 60%. Super helpful and knowledgeable. Sorry for all the questions, new to the efi world. After speaking with Holley Tech Support and Tech Support from where I purchased the systemthey decided to replace it. I have been able to get it pretty 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. 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. I think I figured some of my problems outI'll try to explain. A couple of those and you should feel it getting better. 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. :-). I believe because the TPS is not registering. Two things to keep in mind as you do that. I'll give the ". After this whole process, the car normally rotates without a very abrupt pedal. Or is there something else I should Fuel Prime Multiplier is primarily a benefit to throttle-body based EFI systems. I've read that a spacer with 4 individual holes will solve this, but after I installed the progressive linkage the noise went away!! Camshaft is M-6250-B303 .480 lift intake & exhaust, duration at .050 is 224 degrees for intake & exhaust. If you go the other way then you might find that the IAC zero's out when the fans are off. 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. 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. I followed the instructions and set the IAC to 2-9% when warm with idle at 850 RPM. It sounds like you need a bit more of a fuel squirt on acceleration, Brett. It is always best to get the base map as close as possible before adding acceleration enrichment. I have driven it a few times maybe 100 miles or so. You can drop it down and you will find it will behave more like you expect. I presume your idle speed table doesn't increase at 200 degrees? Idle quality is great, RPM is good, sometimes IAC is jumping around from 35 to 60. 34K views 1 year ago Holley Sniper How to Set The IAC Idle air Control in 5 minutes or less. I have adjusted many settings and eventually mess it up and go back to the original map. It then started working normally again. Chris, I recently installed my Sniper and have an intermittent idle problem. I'm so glad you found this helpful--that makes my day!Don't get too concerned about the specific learn percentage.
What Is Judge Sylvia James Doing Now, Why Was My Gun Purchase Delayed, Articles H