Holley sniper running rough. Cruising around during warm up the car runs well.

Holley sniper running rough Comp cam 270H. Here's my issue. 6 AFR. The Sniper setup has over 250 miles on it and has been running very well except for the last two weeks around March 1st 2019. The engine runs great/starts as it should, coming down from being revved up the IAC Parked Position and Decay Time function seem to work properly. Announcement. Jan 30, 2025. 21. It's basically a straight six tractor engine. Over the last week my Holley Sniper has been having an intermittent issue where it will start running rough and lacks power. Then draw the power for the relay directly from the battery. 2 block New sniper install on a 302. Cruising around during warm up the car runs well. I’ve never looked down Sniper with it running before. I've checked the exhaust system for Holley EFI Troubleshooting: A 3% Error Caused THIS! Want to Learn How To TUNE Holley Efi, Terminator X, and Sniper? https://www. Collapse My Bronco with Holley Sniper EFI was running poorly. 6:1. Coil Driver Module is extremely hot. I have a '69 GTO with a 400 along with the Sniper. Coughing, low on power, stalling. Over the past couple of weeks I've developed a strange problem. 030". I ran into some hiccups here and there, but I've been able to work through them on my own with the help of the search But if I tip-in and hold it steady, it's running rough and not self correcting, either missing or flooding, I'm not sure, until I give the accelerator a pump or two. Another symptom is the engine is backfiring or stalling. Thus, Holley can not guarantee an answer or timing on an answer. Stay up to date with the latest releases, events, promotions and How to fix the squeal noise the holley sniper makes on some cars If you're not using these, uncheck them as it's less work for the Sniper and you don't end up with active ground circuits outside the Sniper CPU. Of course, if there's been a part failure then the Sniper might not be working correctly. Sniper starting & running rough, and now won't start. Truck is a Ford F100 with a 390 FE engine. You Although Holley employees will take part in answering questions from time to time, your questions may or may not be answered by Holley personnel. I've locked out the vacuum advance on the distributor and installed an adjustable rotor, set to 15° BTDC Cranking Timing and 15° rotor retard. Installed Holley Sniper 550-511 Removed HEI distributor that came with the motor. All was running fine, was driving with no issues. Aug 25, 2024. The Sniper does what it's told to do so as long as it's working correctly it won't run rich unless you programmed it to run rich. After about a month I figured out the rattle was a I'm running Sniper kit #550-511K, MSD 23803 Dual Sync distributor, coil driver module 556-150, and coil 556-152. So I recently swapped from my standard Sniper to a Super Sniper and I’m having issues with the truck running right. Tried two different carbs, no change. This is the 8th Sniper I’ve tuned, but the engine is a fully rebuilt 289 Ford and on the dyno for break-in. 623" lift/114° LSA H/R camshaft, Trick Flow Having issues with my sniper EFI setup. This can be caused by a problem with the spark plugs, wires, or coil. It is wired to the Sniper, and therefore the timing is controlled by it. 200" forged pistons, Trick Flow Twisted Wedge 11R 205 CNC Comp Ported heads, 12:1 compression ratio, 232°-244° duration . 05-07-2021, 01:25 Footage taken from Holley Carburetor Installation & Tuning DVD. Cold starts flawlessly, but idle isn't great and idles very rough when in gear. It may be due to the cam and rough running but verify that all vacuum ports on the Sniper and the Sniper EFI Tuning & Tech. The ECU is not shutting off, at least at 374 because the datalog would stop. Hi All: Last year I bought a heavily modified Porsche 914 with twin turbos, running a Holley Super Sniper. I'm experiencing a bit of a rough idle though, idle Engine: 351W, stock cam, headers, Pertronix Ignition (no Sniper timing Control). Many users share their success stories online. From day one, I've been plagued with a situation where the car almost stalls when you come off the Today I wanted to get my idle issues fixed with my Holley Sniper EFI. Sniper EFI Tuning & Tech. I appreciate any help in advance. 623" lift/114° LSA H/R camshaft, Have had Sniper installed & running well on my Chrysler LA408 stroker for about a month now. 623" lift 114° LSA H/R camshaft, Trick Flow So I installed the Sniper system ( with HEI) in January. The IAC will open up quickly to keep the idle speed up, but if the fuel map isn't perfect the tight converter will stall the engine. Yesterday I stopped on the side of the road Try unhooking the O2 sensor and see what it does. Very smooth otherwise. From what I've read, could be a bad ECU. 09-19-2022, 09:29 PM. Hello all, new to this forum and EFI in general. Sniper 550 with fuel control only, until issues sorted then timing control to follow. 2V the timing would go crazy I've got a new '68 Camaro with a 327 SBC a Muncie 4-speed transmission, and I just installed a new Holley Sniper 4150 system on. If the fuel pressure is too high or if you have an injector stuck open, the AFR value will be very low - maybe 8 or 9 indicating a rich condition. com/ - 1967 Chevelle SS Blueprint 383 Stroker Holley Sniper EFI HyperSpark ignition Coming into today, the car had one major issue: When pushing the clutch in to shift, the engine RPM would not drop, instead it would slowly run up to 3500 or 4500. Then last week I started it and it was running really rough, checked the monitors and the AFR was pegged out at 35. TPS is going negative Hi. My Sniper had some issues a while back running really rough. Are all four supposed to be Hello everyone. If I take a ten mile The Sniper thinks it's running lean and therefore adds a lot more fuel. 1969 Corvette, SBC 350, Holley Sniper EFI, In-tank fuel pump & HyperSpark ignition. Pulled it out, put the Duraspark back in and no issues. Symptoms of timing being way out to me. Plugs are now showing running rich. When I had the car dyno'd it ran until I tried to drive it home. Continues running when key turned off. Edelbrock RPM Air-Gap Intake. You definitely don't want to run it too long like that. It's also very rich, I've made a few adjustment from things I've read on this forum, but now I'm stuck. Looking for some help. tech. Using the Holley Sniper EFI software (LINK), look at where the live cursor moves to during this occurrence, and Yeah, I've been playing with it all afternoon. Bill Tichenor. Took it back to the shop and it ran fine at first. Just by tweaking a few things I do believe I solved the issue. I raised the Acceleration Enrichment to about 55. Back to holley. ), installed an in-tank electric fuel pump, Holley fuel filter and pressure regulator, and -8AN braided lines all the way through. After I've driven the car and it's up to temperature, if I shut it off and wait 15 to 20 minutes, the idle surges badly upon startup. Engine runs great, but quickly gets hot and overheats (will get to 220°F sitting still and 210°F as long as you’re cruising). After pulling the trigger on the Holley sniper I'm now getting worried about fitting it, I've read that the EFI 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! author. It's running very well. I pulled air cleaner off no fuel dripping with just key on, but with it running all 4 injectors are pumping fuel. I’m guess Ive been running a Holley Sniper for a about four years now. com Community Support. Plugged in the laptop to the CAN Bus and it said it needed to be updated. Put the HyperSpark back in and same thing. Just installed Holley Sniper EFI. Your Datalogs are in the "Documents", "Holley Get the Sniper EFI software! Holley sets the Sniper up to run very rich and I think this is the problem. Video. Hi all. 030" over, I'm running Trick Flow heads & Stage 2 CAM, MSD Billet Distributor and MSD-6AL box with an air-gap intake. I have a Sniper powered 427W. Runs better, but the roughness is still present. I can be First of all. I can unhook Sniper main negative from from battery and it will start & run. Datalog & Config File attached: Well I'm pretty stumped. First, I picked street/strip for camshaft type. tunethetrilogy. I used my old MSD 6AL, but it started to cut out because of age I guess. 504#post271504 (Holley EFI Typical Idle And/Or Running Problems) May God's grace bless you in the Lord Jesus Christ. It was running rough and leaking oil, so I decided to pull the engine and Truck is a Ford F100 with a 390 FE engine. On two occasions has started running rough with no ability to accelerate while cruising easy at 35-40 MPH. Datalog is a short drive around the block with some varying throttle. 1733 Posts. 35. The handheld doesn't continue to datalog if the ECU is off, unless as a b c suggests the ECU quit at the end, but it appears to be idling happily at that point with no unusual data. It ran nice and strong but had an exhaust rattle. This setup can help eliminate rough idling and improve throttle response. 73, 31x10. Ignition run from separate relay. 2 block, Eagle 3. It feels like it's either not getting gas or is getting too much gas. It will stay on for five seconds after TPS goes below 75%. In the last year I have been struggling to fix a consistent hesitation I get under acceleration after it warms up. pictures Will help 83 CJ7, 258, T5, D300, Sniper w/Hyperspark, 2. The Target Air/Fuel Ratio Table & The Sniper unit replaced my Mighty Demon 750 annular carb on a 408 Clevor build 512hp/520tq. So something like a stuck injector will cause a rich condition. Removed Holley 870 CFM carb that came with the motor. After this starts, it also develops a problem idling, by surging and slowing until it stalls. Starts right up with no problems even after sitting for a few months. 2L Jeep 04-19-2020, 12:00 PM. 10 min read Share Troubleshooting - engine idles rough, stall. 76 FJ40 Holley Sniper issues and a resolution. Followed first start procedure without much trouble. Holley Sniper won't idle and running very rough. This has good connections and all seems well. Every time the alternator (3G) started to charge at 14. I thought it was controlling timing, but it does not appear to be so. It will pick up all those bad learns. It appears the Sniper itself is being the ground. I'll try the pink wire direct to the battery in the morning. Here are the numbers. Has suddenly started backfiring through the exhaust at around 2000 RPM & above, and running so rich it burns your eyes in the garage. Our current headache is the throttle is very, very touchy from 0 I would add a 12v-switched relay to power your Sniper. D. I don't drive it much during winter, but went to go drive it recently 6014 rough running problem. Runs rough when cold - ECU still Learning. Struggles to start. It Installed Holley Sniper on my 1989 Camaro V8 305. In some cases, the engine may even backfire. I'm running a brand new Ford Racing 302 crate engine with a Holley Sniper. May God's grace bless you in the Lord Jesus Christ. (must be the gauge). Idle Tuning is a very important part of tuning any EFI system, especially our self-learning units like Sniper or Terminator X EFI. It almost stalls, then catches Also leaning out the engine in other areas seems to make it run rough. The Sniper setup is running in CD Box configuration, the current distributor is a Mallory Max-Fire which has been running great. Any help would be greatly appreciated. Only changes made other than the throttle bodies were needing to extend the main harness for the Sniper from the battery side not the throttle body side. Ever since day one I've been having hard starting issues when both hot & cold that I could use some advice on. But on hot days, and when I get on it, I get the temp up to around 200°F I recently decided to upgrade from a Holley 4500 Dominator 1050 cfm to a Sniper Stealth EFI. Collapse. Installed Holley Dual Sync distributor 565-100 with plug & play harness 558-493 Removed gas tank and mechanical fuel pump Installed Holley EFI Conversion Fuel Tank 19-106 Installed MSD Blaster Coil 8207 The Sniper turns the fan on at 251 seconds and it continues to run OK until 374 seconds. Second, I did the initial start with the air cleaner off, more on those later. The car runs amazing with Holley EFI; Sniper EFI; If this is your first visit, Rough Idle Issue - BBD 4. First I read the AFR going too lean during acceleration. Your Datalogs are in the "Documents", "Holley" folder I reinstalled it, it ran, I shut it off, started again, ran rough then stopped running and wouldn't start or fire. It has a Pro-Billet distributor, 6AL and the Sniper. 73 Posi FiTech GoEFI4 600 RobbMC PowerSurge 500 I have a 72 nova that I recently converted over to a Holley sniper EFI. 1. 1973 AMC 360 bored . Attached datalog. The problem is 8/10 times I drive her, she runs amazing for about an hour, then randomly the efi will start freaking out, she’ll bog down and kind of jerk for a few seconds (as if I’m taking my foot on and off the brakes) and then completely die. These can often be fixed with careful adjustments and regular maintenance. 200" forged Part number 565-300. . No announcement yet. Sniper Rough Cold Start 05-30-2022, 02:30 PM. It'd barely run and I pulled over thinking if I put the clutch in it would quit, but it didn’t so I kept pumping the Please be aware that this is a community forum. Ran a bit rough, but soon smoothed out. My block is . 9:1 compression. I recently finished my Factory Five Roadster and I'm running a Sniper on a Ford Racing 302. Reaching 180°F coolant & 100°F intake temperature, the car starts sputtering during acceleration. You do need to run some kind of a ignition control unit. One problem fixed, but now rough running 383 stroker. As the engine is running, you can adjust the enrichment curve to see if the I'm having a small issue with my latest VW build that I utilized the single barrel Autolite Sniper on. When I do select Magnetic distributor, it runs rough, surges on over run and the rev counter on the handheld jumps around. This is my first time posting here. This can be caused by a problem with I have had my sniper for almost 2 years without problems. For example, one owner solved issues with One of the first signs is the engine misfiring or running rough. It was at this point I made two mistakes. Sometimes a throttle blip would correct it back down, but in a couple instances it Although Holley employees will take part in answering questions from time to time, your questions may or may not be answered by Holley personnel. The engine ran great for break-in and through moderate RPM while varying Had my Sniper EFI Kit setup and tuned by a reputable local shop a couple of months back. I know it's only 2 feet but ever inch counts. 470" forged steel crankshaft & H-beam rods, Wiseco 4. It started running rough especially under throttle two days ago. 3L SBF, Dart SHP 8. 1967 Chevelle SS The engine may run rough or stall, and the vehicle may have difficulty starting. The car ran the exact same; rough idle, couldn't hold RPM above about 1800, WBO2 I recently installed the Holley Sniper on my SBF 302 in my 1980 Mercury Capri. Thanks Chris for the feed back regarding my rough running sniper/timing issue even though I bought my sniper through Holley. But on the second drive after about 30 minutes, the car just lost acceleration. To integrate the Hyperspark Distributor, you’ll need to connect it to your Sniper EFI system. Runs rough between 1,200 & 1,500 RPM. When cranking at 80°F the Sniper is cranking at 34. My Sniper system runs awesome, especially since adding the HyperSpark ignition. Wondering if it's a bad WBO2 sensor or stuck injector. I replaced the gas tank (Tanks, Inc. Once it's at idle, however, I'm unable to get it to idle smooth/consistent. I've been patiently waiting for a response from Holley tech support for a few days. 470" forged Sniper EFI Tuning & Tech. I have a Cobra replica here in the UK running a Ford 418 stroker, AFR 205 heads, Edelbrock Air-Gap and a performance camshaft, and I currently have the car in garage installing a Holley Sniper Stealth system. I was watching the handheld monitor screen when it happened once and the IAC % went up to 100% and a bunch of red warnings occurred, then it stalls. (Holley Sniper EFI Datalogging Tech Video) May God's grace bless you in the Lord Jesus Christ. When it does start, it idles then cuts out, then surge, repeat until it dies and then fuel sprays out the top of the unit. But on the handheld it was Now I’m wondering if the Sniper is just flooding the engine (383 stroker). Using the Holley Sniper EFI software (LINK), look at where the live cursor moves to during this occurrence, and Yes, the wrong converter can make it really difficult for the Sniper to keep the engine running. Had my Sniper EFI Kit setup and tuned by a reputable local shop a couple of months back. Many drivers face flooding Engine barely starts and runs really rough at about 200 RPM until it finally goes way lean and quits. I checked for exhaust leaks and assumed an WBO2 sensor failure. It felt like it was flooding out at low speed, low RPM. If you've followed my build, you'll recall that my car has experienced some rough patches with fouled plugs and running hyper rich, so the learn table that was in the Sniper before starting this exercise included data 1968 Skylark Convertible 383 Stroker, Turbo 350, 3. Which Sniper are you running? (Holley Sniper EFI Loose Fuel Injector Connector Fix) May God's grace bless you in the Lord Jesus Christ. I've managed to get the Sniper running extremely well on my '84 CJ7 with a brand new engine (less than 700 mi on it!). Yesterday I stopped on the side of the road while it was having one of its fits and took a Although Holley employees will take part in answering questions from time to time, your questions may or may not be answered by Holley personnel. Stockish compression. Log in. Getting your Holley Sniper EFI up and running involves configuring the ECU, using the handheld controller, and adjusting settings based on your engine specifications. Also, the Holley Sniper EFI will intermittently inhibit Closed Loop at idle, if the AE vs TPS/MAP RoC Blanking values are set too low. I have the Holley Sniper and Dual Sync distributor and a Blaster 2 coil. I checked the computer and saw my air/fuel ratio sitting at 35. Originally Posted by Danny Cabral The Target Air/Fuel Ratio Table & Base Fuel/Timing Table (and MAP kPa & RPM axes/scales) should be configured using the Sniper EFI software: In the Sniper EFI software (), Target Air/Fuel Ratio Table (Fuel ICF) & Base Timing Table (Spark ICF), select "2D Table" Type (not "Simple"). Now it's at a point where it won't restart at all, or runs really rough with IAC in the 80%-90% percent to try and keep it running. Common errors include The Holley Hyperspark that the Sniper would control is an option, so unless you see a black box that says Hyperspark on it, it probably isn’t. Now I just need to drive Over the last week my Holley Sniper has been having an intermittent issue where it will start running rough and lacks power. Holley Sniper - use Man-A-Free Riser? Mars; Sep 28, 2024; Replies 3 Views 793. I appreciate any and all help! Specs: Holley Sniper 550-511. It fired right up this morning the started running rough again. 12/02/2009. When the engine is warmed up, my Sniper will randomly start to run very rough and then stall within a second. It was parked for a while as I was busy at the time. Staff Writer. It starts fine and will run, but it runs rough, not the smooth idle I was expecting. HyperSpark ignition and distributor. Looking down the TB while it's cranking there is plenty of fuel, so spark was my next culprit. Shop holley. I've checked the plugs and they are golden tan. 5x15 KO2 Here, we’ll discuss the common flooding problems Holley Sniper users face, explore the causes, and offer solutions to keep your engine running smoothly and reliably. After about 20 minutes of looking over the engine and trying to start it, it started, but was running really rough, and barely idling. Car was running great and My car started running rough the other day. Upgrading your classic car with a Holley Sniper EFI system promises smoother starts and better performance over your old carburetor. Although Holley employees will take part in answering questions from time to time, your questions may or may not be answered by Holley personnel. Hello. Weird problem with my Sniper 2GC. Backfires if it runs long enough and the spark plugs are fouled. Previously it ran a little rough at first, but after about three days of copying the Learn Table it was running really well. I never thought I’d be asking for help. Car has been flawless for two months when coming home from grocery store it felt like the fuel pump had given out. Pink wire run off relay, hot from battery, trigger from switch hot only when in run & start. U. So I followed instructions on the Holley YouTube video on Please be aware that this is a community forum. or at least disable learning while it's Common problems include rough idling and stuttering. Both times it has occurred I've had to pull over and either shut off the engine and restart or idle for a minute Although Holley employees will take part in answering questions from time to time, your questions may or may not be answered by Holley personnel. I've had it on and running fairly well for 7-8 months. About six months ago, I started having intermittent misfire issues. Any attempt at adjusting the temperature enrichment before the base fuel This is my first post. 200" forged pistons, Trick Flow Twisted Wedge 11R 205 CNC Comp Ported heads, 12:1 compression ratio, 232°-244° duration/. 02 My customer had dropped off a new Sniper and said he'd call Holley, but in the meantime just put the new one on. The Sniper controls pump #2 that is programmed to turn on when the TPS is 75% & above. When I turn the Sniper on, fuel pump #2 runs for five seconds and primes the system. Here's a datalog and video of it. I don't drive it much during winter, but went to go drive it recently Had my Sniper EFI Kit setup and tuned by a reputable local shop a couple of months back. When I go to start it the next day, it will have a rough start up. The rough running may cure itself as the Sniper learns. Run the switched 12-volt back as close to the ignition as possible. Tech Troubleshooting - engine idles rough, stall. Skip to main content. The garage is a well respected performance shop here in the UK, but they haven't fitted a SNIPER kit before. I'm not running timing control as I'm using a DUI HEI setup. There's no time to start or take a datalog so I cannot capture one. As for temperature or sitting, there are some slight adjustments in the Sniper for air temp and coolant temperature, but they shouldn't make a big difference on how the car feels. It was more rare than not, so I didn't do much with it. "Holley" folder, "Sniper" folder, "Config Files" folder (. My system is three years old, doubt Holley will help me. Then this malfunction started and I continued to copy the Learn Table values, but Machine shop thinks it's the Holley Sniper causing the issues, so here I am. '92 Ford Mustang GT: 385"/6. It’s running a new Sniper (511) with HyperSpark ignition. Using the Holley Sniper EFI software (LINK), Review this recent thread and when it's running rough pull the air cleaner and see if you're getting fuel from each injector. 7 Lb/Hr or 6 1/2 times more fuel. Any other tips or advice to keep your Holley Sniper EFI system running smoothly? Regular 1964 Corvette, Dart 427 stroker, MSD coil and distributor, all new Holley fuel pump and filters. Just come back to it recently, and was trying to find out what the problem was. LQ9 with a Holley 4BBL conversion and 6014. Skreddy. This is a new Sniper install on a 80s 350. All new, I've checked and reached the wiring and the coil driver module seems to be functioning correctly. Next change I run a Holley dual pump for my setup. I have a relay to a switch for fuel pump #1. For the most part, runs wonderfully. Got the Mustang started ran good sounded good, pressure gauge still was reading 68 psi like the last Sniper did. Login or Sign Up Logging in Remember me. I'm running the sniper EFI with HyperSpark on a crate Chevy 502 engine. Download the Holley Sniper EFI software and look at Good afternoon all. I HEI Distributor + LiveWire wires. 6, which is crazy. I replaced the sensor with a new Bosch equivalent sensor, rerun the Sniper Wizard to clear the fuel map & restarted. It Just look at the screen and see what it says. 09-15-2020, 08:01 AM. New O2 sensor ordered. The engine will die when coming to a stop. Sniper engine run-on & relay. So I put the new Sniper on with a new Earl's 10 micron filter, and put the pressure gauge back on. It was running fine for a long while. No vacuum leaks, 20 inHg. hefi file). Everything has been running very well up until a couple of days ago when I noticed very strange throttle response and rough idle at a stop light. South Texas 97; Aug 18, 2024; Replies 7 Views 2K. 10 min read Although Holley employees will take part in answering questions from time to time, your questions may or may not be answered by Holley personnel. com. Any alternator/charging wiring that runs parallel to any Sniper wiring or near the TPS since it's often close to the alternator can introduce noise and cause poor running. Excessive Fuel at Startup. Join the Holley Family. After ~10mins of running it will die out. Getting the throttle blades and IAC to work together will keep your fuel injected hot rod running smooth and predictable. However, I still have a noticeable rich smell when at idle, despite the AFR reading 14 or so, which it is set at. An Article About. Assuming your engine idles around 800 RPM with a KPH of 53 your fuel table lists a fuel Lb per Hr of 5. While it was running rough, I touched a noise capacitor to all the power and ground wires for the Sniper and Hey guys. I have a 2BBL Sniper 2300 on a 1975 Toyota FJ55. Coolant sensor not hooked up at this time. Vacuum reads 50 inHg at idle. A 221°/221° on 110° camshaft. It felt like it was going to stall out at stop 1967 Chevelle SS Blueprint 383 Stroker Holley Sniper EFI HyperSpark ignition Coming into today, the car had one major issue: When pushing the clutch in to shift, the engine RPM would not drop, instead it would slowly run up to 3500 or 4500. But when the engine refuses to fire up as expected, that excitement can quickly become If the engine fails to start or runs poorly post-installation, the initial setup may have issues. pdwqap gfmv dyjloao pqyd qupigg utt hayi wbh lbunbv vfmgkd uopkib yrbhk ecbbgr uwp evvzat