Results 1 to 2 of 2

Thread: Useful Sniper EFI Information

  1. #1

    Default Useful Sniper EFI Information

    Sniper EFI Specific Tech Videos
    Video on Installing a MSD Magnetic Distributor with Timing Control: Magnetic Distributor with Timing Control Install
    Installing a Holley Dual Sync Distributor with Timing Control: Holley Dual Sync with Timing Control Install
    Datalogging with Sniper EFI: Datalogging with Sniper EFI
    Updating firmware for Sniper EFI: Holley Sniper EFI Firmware Update

    Here's a link to some flow charts to help Troubleshoot your Sniper EFI: Troubleshooting Guide

    It's important to note that the Sniper EFI system will not fix an engine that's not mechanically sound.
    If the engine has mechanical issues, those need to be addressed before installing & troubleshooting the Sniper EFI.

    Below are also some helpful Holley EFI videos to prevent some of the common installation errors Holley Tech sees often with the Sniper EFI.
    The videos use HP & Dominator ECUs in the examples, however, the content applies to the Sniper EFI as well.

    Holley EFI Video on Potential Problems: Potential Install Problems
    Holley EFI Video on Bad Wiring Practices: Bad Wiring Practices
    Holley EFI Video on Protecting Wiring Properly: Protecting Wiring Properly (Pay specific attention to the WBO2 sensor cable routing from hazards, such as the exhaust and moving parts.)
    Last edited by Matt; 03-21-2018 at 09:05 AM.

  2. #2
    Join Date
    Dec 2009

    Default Sniper EFI Troubleshooting & Technical Information

    Sniper EFI Software Help Information/Instructions:
    ‒ On the top Toolbar, click "Help" & "Contents". This opens all Help topics.
    ‒ When navigating the Sniper EFI software, click "Help ?" or the F1 key.
    ...This automatically opens the definitions for that specific parameter. (Holley Sniper EFI Software & Holley 558-443 CAN/USB Dongle) (Holley Sniper EFI Optional Comm/Data Cable Accessories) (Holley Sniper EFI Help Manual - EFI Software, Tuning & Datalogging) (Holley Sniper EFI Instruction Manual) (Holley Sniper EFI Quick Start Manual) (Holley Sniper EFI Troubleshooting Guide) (Holley Sniper EFI SD Card Contents) (Holley Sniper EFI Technical Information & Troubleshooting)
    If you want someone to help you by means of a remote tuning session, I'd contact:
    Andrew B. @projectgattago, Chris Myer at or Richard Nedbal (FastManEFI) at

    EFI Software & ECU Firmware Versions:
    EFI SOFTWARE: Click "Help" tab (top toolbar) & "About Holley Sniper EFI".
    ECU FIRMWARE: Click "Sync With ECU" & "Get ECU Info" (Key-on/USB connected).
    The latest EFI software & ECU firmware can be downloaded here: (Holley EFI Technical Library) (How To Update ECU Firmware)
    Before updating firmware, ensure the current Global File is saved somewhere, since it will be erased from the ECU.
    The EFI (laptop/PC) software, ECU firmware & touchscreen unit must all be version compatible (LINK).

    Sniper EFI Technical Information & Troubleshooting: (Holley Sniper EFI Software) (Holley Sniper EFI 3.5" TSLCD & ECU Firmware Update Info) (Holley Sniper EFI Incompatible 3.5" TSLCD Firmware) (Holley Sniper EFI SD Card Contents) (Holley Sniper EFI 2300 2BBL Quick Start Guide) (Holley Sniper EFI 2300 2BBL Instruction Manual) (Holley Sniper EFI Quick Start Manual) (Holley Sniper EFI Instruction Manual) (Holley Sniper EFI Troubleshooting Guide) (Holley Sniper EFI Help Manual - EFI Software, Tuning & Datalogging) (Holley Sniper EFI 3.5" TSLCD Connector Disconnect) (Holley Sniper EFI 3.5" TSLCD Gauge Background Colors) (Holley Sniper EFI 3.5" TSLCD - Change Temperatures To Celsius) (Holley Sniper EFI Alternator Information For EFI Applications) (Holley Sniper EFI A/C IAC Kick, Electric Fan #1/#2 Wiring & A/C Shutdown Info) (Holley Sniper EFI Rev Limiter Verification Feature Disabled) (Holley Sniper EFI Tachometer Wiring Information) (Holley Sniper EFI RFI/EMI Issues) (Holley Sniper EFI 4-Hole Spacer, Eliminates IAC Whistle Noise) (Holley Sniper EFI Dual-Plane Intake Manifold Use)! (Holley Sniper EFI High Idle Thread - Read Posts #1 & #2) (Holley Sniper EFI Fixed Orifice PCV Valve Thread) (Holley Sniper EFI Fuel System Plumbing - Posts #2, #6, #14) (Holley Sniper EFI Fuel Pressure Tester/Gauge) (WBO2 Sensor Test At End Of "Wideband O2 Sensor Notes") (Holley Sniper EFI Progressive Secondary Throttle Linkage Requirements) (Throttle Blade Centering Misalignment & Secondary Shaft Coiled Spring Tightness) (Holley Sniper EFI Replacement Parts) (Holley Sniper EFI Replacement CTS) (Holley Sniper EFI Main Harness Wire Gauge List) (Holley Sniper EFI Retrieve, Save & Upload GCF - SD Card & Laptop/PC Usage, Pages 72 & 73) (Holley Sniper EFI Save GCF On SD Card & Laptop/PC Usage, LINK - Page 73) (Holley Sniper EFI Datalogging Tech Video) (Holley Sniper EFI Assembly Line At Holley Facility) (How To Install A Holley Sniper EFI System) (Holley Sniper EFI - Avoid Magnetic Ignition Type, Use Hall-Effect/HyperSpark Distributor) (Holley Sniper EFI, HyperSpark Distributor, CDI Box & Coil Wiring Diagram - Page 3) (Holley Sniper EFI - Dual Sync Distributor Installation Tech Video) (Holley Sniper EFI - Dual Sync Distributor Installation Tech Video) (Holley Sniper EFI - MSD Distributor Installation Tech Video) (Holley Sniper EFI - MSD Distributor Installation Tech Video) (Holley Sniper EFI - MSD Distributor & CDI Box Installation Tech Video) (Holley Sniper EFI Technical Information & Troubleshooting)

    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 (LINK), Target Air/Fuel Ratio Table (Fuel ICF) & Base Timing Table (Spark ICF), select "2D Table" Type (not "Simple"). The Target Air/Fuel Ratio Table & Base Timing Table can then be properly configured & tuned for any engine. I always suggest taking notes of your current distributor's ignition timing specs/curves beforehand, and then program the Base Timing Table accordingly. (Sniper EFI Software & Holley 558-443 CAN/USB Dongle) (Sniper EFI Optional Comm/Data Cable Accessories)
    Originally Posted by Danny Cabral
    Is the Sniper EFI Learning? Is the ignition timing synchronized? Is the fuel pressure 58-60 psi (LINK)? IAC Position
    of about 5% at hot idle? Check for ignition misfires/RPM signal problems, exhaust leak upstream of WBO2 sensor,
    or if the WBO2 sensor (or other sensor) has failed and corrupted the Learn Table. Look at the Data Monitor/Gauges.
    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. (Holley Sniper EFI Help Manual) (Holley Sniper EFI Troubleshooting Guide) (Holley Sniper EFI Fuel Pressure Tester/Gauge)
    Originally Posted by Danny Cabral
    The Sniper EFI doesn't have the same TPS Autoset function as the Terminator, HP & Dominator ECUs. The Sniper EFI calibrates the TPS sensor at every key-on event. If replacing the TPS, the TPS sensor is located at the end of the primary throttle shaft, opposite end of the throttle lever. It's slotted, so install it in the same position. Holley 543-111 TPS or Standard Motor Products TH191 TPS. (Replacement Sensors For Holley EFI - Auto Parts Store)

    Sniper EFI Idle Setting/Throttle Blade Setting (Holley Sniper EFI Quick Start Manual):
    Once the engine is up to operating temperature, the idle speed can be set to what was configured in the Wizard.
    To do this, open up the Initial Startup gauge screen that was used in section 17.0. With the vehicle in neutral,
    adjust the idle screw until the IAC Position reads between 2 & 10%. While adjusting the idle speed screw, if the
    TPS Position begins to read higher than 0%, cycling the ignition switch will recalibrate the TPS back to zero.
    This explains the idle speed screw/IAC Position % relationship that must be properly set for idle control.
    NOTE: Do not attempt to set the Target Idle Speed and IAC Position until the engine is above 160°F! (Holley Sniper EFI Quick Start Manual - "Idle Setting/Throttle Plate Setting", Page 12)! (Sniper EFI High Idle Thread)

    * Initial Baseline Idle Speed Screw Setting *
    Sometimes the throttle blades are so far off adjustment, turning the idle speed screw triggers the IAC Hold Position.
    If this happens, the throttle blades will require a baseline setting without the IAC valve altering this adjustment.
    This must be accomplished with the engine at hot idle. Be careful of dangerous fan and belt driven components.
    With the air filter previously removed, block off the IAC air inlet port with your finger or a strong piece of tape.
    While temporarily ignoring the IAC Position, adjust the idle speed screw to the Target Idle Speed RPM (in Idle ICF).
    Turn engine off (remove tape). With the key-on/engine-off, perform a TPS Autoset. Cycle key off & restart engine.
    Now only a minute adjustment will be required to achieve an IAC Position of about 5%. Perform a final TPS Autoset. (General IAC Information - Read "IAC NOTES")
    Originally Posted by Danny Cabral
    For further assistance, post your Config File and a short datalog of this occurrence for us to analyze.
    Also, review the datalog and inform us of exactly where in the datalog (time/seconds) the problem occurs.
    Datalog & Global Files can be linked to a document hosting website. I use
    Files can also be "zipped" (compressed zipped folder) & attached directly to a forum post ("Go Advanced" & "Attachments").
    Your Config File is in the "Documents", "Holley" folder, "Sniper" folder, "Config Files" folder (.hefi file).
    Your Datalogs are in the "Documents", "Holley" folder, "Sniper" folder, "Data Logs" folder (.dl file).
    Someone will analyze/troubleshoot the problem & offer advice. (How To Record & Email A Datalog)
    Overlay the datalog onto your Config File, and pay special attention to the center paragraph in blue print:
    Originally Posted by Danny Cabral
    Quick Datalogger Information:
    Always provide data, not just symptoms. Is the AFR & ignition timing optimized? Overlay the datalog onto your Config File.
    Ensure the Target A/F Ratio table is properly programmed for your engine. Ensure the ECU is "Learning" (Learn Table LINK).
    Scroll through the datalog to the problem area. Then look exactly where this happens on the Base Fuel & Timing Tables. Scrutinize:
    RPM, MAP, MAT, TPS, CTS, IAC, Target AFR, AFR Left, CL Comp, Ignition Timing, Duty Cycle, Fuel Flow, Fuel Pressure & Battery. When the engine is tuned & running well, you should decrease the Closed Loop & Learned Compensation Limits % to lock in a good tune.

    Using the Holley Sniper EFI software (LINK), look at where the live cursor moves to during this occurrence, and
    manually tune that area of the Base Fuel Table (enrich or lean) & Base Timing Table (optimize ignition timing).

    I find the most helpful datalog function, is overlaying the datalog on your Config File.
    I'm in the habit of using the datalog Overlay feature every time I review a datalog.
    Click on "Datalog" (on the top Toolbar), "Activate Overlay", then "Open Data Log".
    You can literally "playback" a recorded event, and watch it as it happened on any screen.
    Minimize (shrink) the datalog window, and move it to the bottom of any Config File screen.
    Then click & scroll anywhere on the datalog, and watch it playback on your Config File (EFI software). (Holley EFI Datalogger Instructions) (Datalog Information - Read "NOTES") (How To Record & Email A Datalog) (Closed Loop Datalog Tuning - Posts #2, #4 & #6) (Holley Sniper EFI Datalogging Tech Video)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
About us
Holley has been the undisputed leader in fuel systems for over 100 years. Holley carburetors have powered every NASCAR® Sprint® Cup team and nearly every NHRA® Pro–Stock champion for four decades. Now, Holley EFI is dominating the performance world as well as our products for GM's LS engine. Holley's products also include performance fuel pumps, intake manifolds & engine dress–up products for street performance, race and marine applications. As a single solution, or partnered with products from other Holley companies - Hooker Headers, Flowtech Headers, NOS Nitrous, Weiand, Earl's Performance Plumbing, or Diablosport - Holley products can give you the edge you need over the competition.
Join us