Holley sniper running rough. This is a new Sniper install on a 80s 350.

Holley sniper running rough I HEI Distributor + LiveWire wires. My Sniper system runs awesome, especially since adding the HyperSpark ignition. Second, I did the initial start with the air cleaner off, more on those later. Reaching 180°F coolant & 100°F intake temperature, the car starts sputtering during acceleration. Stockish compression. Weird problem with my Sniper 2GC. D. Plugged in the laptop to the CAN Bus and it said it needed to be updated. It appears the Sniper itself is being the ground. Skreddy. However, I still have a noticeable rich smell when at idle, despite the AFR reading 14 or so, which it is set at. 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. Log in. 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. So I followed instructions on the Holley YouTube video on Please be aware that this is a community forum. I'm running the sniper EFI with HyperSpark on a crate Chevy 502 engine. Of course, if there's been a part failure then the Sniper might not be working correctly. So something like a stuck injector will cause a rich condition. An Article About. After this starts, it also develops a problem idling, by surging and slowing until it stalls. 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. Coil Driver Module is extremely hot. Many drivers face flooding Engine barely starts and runs really rough at about 200 RPM until it finally goes way lean and quits. 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 felt like it was flooding out at low speed, low RPM. It was at this point I made two mistakes. Video. When I go to start it the next day, it will have a rough start up. Ignition run from separate relay. 470" forged steel crankshaft & H-beam rods, Wiseco 4. Then last week I started it and it was running really rough, checked the monitors and the AFR was pegged out at 35. 9:1 compression. Although Holley employees will take part in answering questions from time to time, your questions may or may not be answered by Holley personnel. You do need to run some kind of a ignition control unit. I thought it was controlling timing, but it does not appear to be so. It almost stalls, then catches Also leaning out the engine in other areas seems to make it run rough. I have a '69 GTO with a 400 along with the Sniper. Datalog & Config File attached: Well I'm pretty stumped. One problem fixed, but now rough running 383 stroker. I'll try the pink wire direct to the battery in the morning. Just installed Holley Sniper EFI. 73 Posi FiTech GoEFI4 600 RobbMC PowerSurge 500 I have a 72 nova that I recently converted over to a Holley sniper EFI. From what I've read, could be a bad ECU. 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. or at least disable learning while it's Common problems include rough idling and stuttering. 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. I know it's only 2 feet but ever inch counts. 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 don't drive it much during winter, but went to go drive it recently 6014 rough running problem. Truck is a Ford F100 with a 390 FE engine. It feels like it's either not getting gas or is getting too much gas. In some cases, the engine may even backfire. 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. Login or Sign Up Logging in Remember me. 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. I'm running a brand new Ford Racing 302 crate engine with a Holley Sniper. Put the HyperSpark back in and same thing. Just come back to it recently, and was trying to find out what the problem was. 623" lift/114° LSA H/R camshaft, Trick Flow Having issues with my sniper EFI setup. Ever since day one I've been having hard starting issues when both hot & cold that I could use some advice on. Got the Mustang started ran good sounded good, pressure gauge still was reading 68 psi like the last Sniper did. First, I picked street/strip for camshaft type. Thanks Chris for the feed back regarding my rough running sniper/timing issue even though I bought my sniper through Holley. 7 Lb/Hr or 6 1/2 times more fuel. 504#post271504 (Holley EFI Typical Idle And/Or Running Problems) May God's grace bless you in the Lord Jesus Christ. 05-07-2021, 01:25 Footage taken from Holley Carburetor Installation & Tuning DVD. Comp cam 270H. It is wired to the Sniper, and therefore the timing is controlled by it. 73, 31x10. This is a new Sniper install on a 80s 350. It ran nice and strong but had an exhaust rattle. I’m guess Ive been running a Holley Sniper for a about four years now. Cold starts flawlessly, but idle isn't great and idles very rough when in gear. I never thought I’d be asking for help. No announcement yet. 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. Hello. No vacuum leaks, 20 inHg. 1967 Chevelle SS The engine may run rough or stall, and the vehicle may have difficulty starting. It's running very well. 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!). Our current headache is the throttle is very, very touchy from 0 I would add a 12v-switched relay to power your Sniper. The Sniper setup is running in CD Box configuration, the current distributor is a Mallory Max-Fire which has been running great. 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. Over the last week my Holley Sniper has been having an intermittent issue where it will start running rough and lacks power. When I turn the Sniper on, fuel pump #2 runs for five seconds and primes the system. My Sniper had some issues a while back running really rough. 6, which is crazy. Pink wire run off relay, hot from battery, trigger from switch hot only when in run & start. 09-19-2022, 09:29 PM. 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 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. 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. I've had it on and running fairly well for 7-8 months. com. It's basically a straight six tractor engine. 09-15-2020, 08:01 AM. A 221°/221° on 110° camshaft. Starts right up with no problems even after sitting for a few months. Took it back to the shop and it ran fine at first. Any help would be greatly appreciated. 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. 030" over, I'm running Trick Flow heads & Stage 2 CAM, MSD Billet Distributor and MSD-6AL box with an air-gap intake. Getting your Holley Sniper EFI up and running involves configuring the ECU, using the handheld controller, and adjusting settings based on your engine specifications. Has suddenly started backfiring through the exhaust at around 2000 RPM & above, and running so rich it burns your eyes in the garage. 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. To integrate the Hyperspark Distributor, you’ll need to connect it to your Sniper EFI system. Yesterday I stopped on the side of the road Try unhooking the O2 sensor and see what it does. I'm not running timing control as I'm using a DUI HEI setup. Tech Troubleshooting - engine idles rough, stall. 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. I used my old MSD 6AL, but it started to cut out because of age I guess. 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. 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. Are all four supposed to be Hello everyone. Very smooth otherwise. Sniper Rough Cold Start 05-30-2022, 02:30 PM. 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. 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. Announcement. 1733 Posts. 200" forged Part number 565-300. Backfires if it runs long enough and the spark plugs are fouled. It Just look at the screen and see what it says. 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. 200" forged pistons, Trick Flow Twisted Wedge 11R 205 CNC Comp Ported heads, 12:1 compression ratio, 232°-244° duration/. I have the Holley Sniper and Dual Sync distributor and a Blaster 2 coil. 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. 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. Once it's at idle, however, I'm unable to get it to idle smooth/consistent. Removed Holley 870 CFM carb that came with the motor. The Sniper controls pump #2 that is programmed to turn on when the TPS is 75% & above. When I had the car dyno'd it ran until I tried to drive it home. Run the switched 12-volt back as close to the ignition as possible. Another symptom is the engine is backfiring or stalling. 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. 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. 6:1. tech. It’s running a new Sniper (511) with HyperSpark ignition. 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. 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. 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. Join the Holley Family. 2 block, Eagle 3. Collapse My Bronco with Holley Sniper EFI was running poorly. I have a 2BBL Sniper 2300 on a 1975 Toyota FJ55. I can be First of all. Followed first start procedure without much trouble. Holley Sniper won't idle and running very rough. It was more rare than not, so I didn't do much with it. While it was running rough, I touched a noise capacitor to all the power and ground wires for the Sniper and Hey guys. Aug 25, 2024. I can unhook Sniper main negative from from battery and it will start & run. 470" forged Sniper EFI Tuning & Tech. I've checked the plugs and they are golden tan. 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. It will stay on for five seconds after TPS goes below 75%. Attached datalog. This is my first time posting here. Many users share their success stories online. 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). LQ9 with a Holley 4BBL conversion and 6014. It has a Pro-Billet distributor, 6AL and the Sniper. When the engine is warmed up, my Sniper will randomly start to run very rough and then stall within a second. Here's my issue. I raised the Acceleration Enrichment to about 55. The Target Air/Fuel Ratio Table & The Sniper unit replaced my Mighty Demon 750 annular carb on a 408 Clevor build 512hp/520tq. U. . 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. I have a Sniper powered 427W. First I read the AFR going too lean during acceleration. Sniper EFI Tuning & Tech. hefi file). 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 replaced the gas tank (Tanks, Inc. 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. 1. (must be the gauge). 2L Jeep 04-19-2020, 12:00 PM. It Installed Holley Sniper on my 1989 Camaro V8 305. Looking for some help. 623" lift/114° LSA H/R camshaft, Have had Sniper installed & running well on my Chrysler LA408 stroker for about a month now. Here's a datalog and video of it. (Holley Sniper EFI Datalogging Tech Video) May God's grace bless you in the Lord Jesus Christ. Runs better, but the roughness is still present. 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. There's no time to start or take a datalog so I cannot capture one. I appreciate any help in advance. All new, I've checked and reached the wiring and the coil driver module seems to be functioning correctly. The car runs amazing with Holley EFI; Sniper EFI; If this is your first visit, Rough Idle Issue - BBD 4. On two occasions has started running rough with no ability to accelerate while cruising easy at 35-40 MPH. I appreciate any and all help! Specs: Holley Sniper 550-511. Bill Tichenor. I’ve never looked down Sniper with it running before. Wondering if it's a bad WBO2 sensor or stuck injector. May God's grace bless you in the Lord Jesus Christ. 200" forged pistons, Trick Flow Twisted Wedge 11R 205 CNC Comp Ported heads, 12:1 compression ratio, 232°-244° duration . 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. com Community Support. New O2 sensor ordered. So I recently swapped from my standard Sniper to a Super Sniper and I’m having issues with the truck running right. Runs rough when cold - ECU still Learning. I'm experiencing a bit of a rough idle though, idle Engine: 351W, stock cam, headers, Pertronix Ignition (no Sniper timing Control). Struggles to start. Coolant sensor not hooked up at this time. Over the past couple of weeks I've developed a strange problem. My system is three years old, doubt Holley will help me. Holley Sniper - use Man-A-Free Riser? Mars; Sep 28, 2024; Replies 3 Views 793. TPS is going negative Hi. When I do select Magnetic distributor, it runs rough, surges on over run and the rev counter on the handheld jumps around. Hi All: Last year I bought a heavily modified Porsche 914 with twin turbos, running a Holley Super Sniper. I replaced the sensor with a new Bosch equivalent sensor, rerun the Sniper Wizard to clear the fuel map & restarted. When cranking at 80°F the Sniper is cranking at 34. It's also very rich, I've made a few adjustment from things I've read on this forum, but now I'm stuck. 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. 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. For example, one owner solved issues with One of the first signs is the engine misfiring or running rough. 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. Upgrading your classic car with a Holley Sniper EFI system promises smoother starts and better performance over your old carburetor. 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. 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. Edelbrock RPM Air-Gap Intake. It was running fine for a long while. The rough running may cure itself as the Sniper learns. But on the handheld it was Now I’m wondering if the Sniper is just flooding the engine (383 stroker). 1969 Corvette, SBC 350, Holley Sniper EFI, In-tank fuel pump & HyperSpark ignition. But on the second drive after about 30 minutes, the car just lost acceleration. About six months ago, I started having intermittent misfire issues. Looking down the TB while it's cranking there is plenty of fuel, so spark was my next culprit. Plugs are now showing running rich. Car was running great and My car started running rough the other day. Symptoms of timing being way out to me. 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. It fired right up this morning the started running rough again. 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. These can often be fixed with careful adjustments and regular maintenance. 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. South Texas 97; Aug 18, 2024; Replies 7 Views 2K. Previously it ran a little rough at first, but after about three days of copying the Learn Table it was running really well. Next change I run a Holley dual pump for my setup. Installed Holley Sniper 550-511 Removed HEI distributor that came with the motor. It starts fine and will run, but it runs rough, not the smooth idle I was expecting. "Holley" folder, "Sniper" folder, "Config Files" folder (. 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. Datalog is a short drive around the block with some varying throttle. Hi all. I checked the computer and saw my air/fuel ratio sitting at 35. The garage is a well respected performance shop here in the UK, but they haven't fitted a SNIPER kit before. 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. I've been patiently waiting for a response from Holley tech support for a few days. Sniper engine run-on & relay. Shop holley. 12/02/2009. 21. 10 min read Share Troubleshooting - engine idles rough, stall. Getting the throttle blades and IAC to work together will keep your fuel injected hot rod running smooth and predictable. 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. Ran a bit rough, but soon smoothed out. tunethetrilogy. I pulled air cleaner off no fuel dripping with just key on, but with it running all 4 injectors are pumping fuel. So I put the new Sniper on with a new Earl's 10 micron filter, and put the pressure gauge back on. HyperSpark ignition and distributor. It will pick up all those bad learns. This can be caused by a problem with the spark plugs, wires, or coil. 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. In the last year I have been struggling to fix a consistent hesitation I get under acceleration after it warms up. I checked for exhaust leaks and assumed an WBO2 sensor failure. ), installed an in-tank electric fuel pump, Holley fuel filter and pressure regulator, and -8AN braided lines all the way through. I recently finished my Factory Five Roadster and I'm running a Sniper on a Ford Racing 302. Continues running when key turned off. Just by tweaking a few things I do believe I solved the issue. All was running fine, was driving with no issues. Collapse. Car has been flawless for two months when coming home from grocery store it felt like the fuel pump had given out. 35. Back to holley. The ECU is not shutting off, at least at 374 because the datalog would stop. Skip to main content. After about 20 minutes of looking over the engine and trying to start it, it started, but was running really rough, and barely idling. After ~10mins of running it will die out. Assuming your engine idles around 800 RPM with a KPH of 53 your fuel table lists a fuel Lb per Hr of 5. For the most part, runs wonderfully. Download the Holley Sniper EFI software and look at Good afternoon all. Sniper starting & running rough, and now won't start. 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. pictures Will help 83 CJ7, 258, T5, D300, Sniper w/Hyperspark, 2. 3L SBF, Dart SHP 8. I have a relay to a switch for fuel pump #1. 030". 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. Runs rough between 1,200 & 1,500 RPM. 2 block New sniper install on a 302. 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. 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. This has good connections and all seems well. Hello all, new to this forum and EFI in general. Tried two different carbs, no change. 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. This is the 8th Sniper I’ve tuned, but the engine is a fully rebuilt 289 Ford and on the dyno for break-in. You definitely don't want to run it too long like that. 76 FJ40 Holley Sniper issues and a resolution. 6 AFR. Pulled it out, put the Duraspark back in and no issues. 623" lift 114° LSA H/R camshaft, Trick Flow So I installed the Sniper system ( with HEI) in January. Then draw the power for the relay directly from the battery. If I take a ten mile The Sniper thinks it's running lean and therefore adds a lot more fuel. Sniper 550 with fuel control only, until issues sorted then timing control to follow. Had my Sniper EFI Kit setup and tuned by a reputable local shop a couple of months back. Every time the alternator (3G) started to charge at 14. Jan 30, 2025. Idle Tuning is a very important part of tuning any EFI system, especially our self-learning units like Sniper or Terminator X EFI. Any attempt at adjusting the temperature enrichment before the base fuel This is my first post. Staff Writer. Here are the numbers. Thus, Holley can not guarantee an answer or timing on an answer. This can be caused by a problem with I have had my sniper for almost 2 years without problems. 1973 AMC 360 bored . It was parked for a while as I was busy at the time. Excessive Fuel at Startup. The engine will die when coming to a stop. 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. 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"). My block is . It started running rough especially under throttle two days ago. Vacuum reads 50 inHg at idle. Coughing, low on power, stalling. 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. Cruising around during warm up the car runs well. This setup can help eliminate rough idling and improve throttle response. '92 Ford Mustang GT: 385"/6. pfqsj adjue qnzfnj tstex dgafom zqdex bnhwjr ktsb mvweeck tzkhe xxqgnt omhvy izt mkyr njhchew