Useful Sniper EFI Information

**Matt** · 07-21-2017, 11:16 AM

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.)

**Danny Cabral** · 07-24-2017, 08:52 AM

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.
https://www.holley.com/support/resou...Fuel_Injection (Sniper EFI Software & Holley 558-443 CAN/USB Dongle)
https://forums.holley.com/showthread...679#post100679 (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.
http://documents.holley.com/techlibrary_199r11259.pdf (Holley Sniper EFI Help Manual)
http://documents.holley.com/199r11369.pdf (Holley Sniper EFI Troubleshooting Guide)
https://forums.holley.com/showthread...8356#post88356 (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.
http://forums.holley.com/showthread....=2760#post2760 (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!
http://documents.holley.com/199r11193.pdf (Holley Sniper EFI Quick Start Manual - "Idle Setting/Throttle Plate Setting", Page 12)
https://forums.holley.com/showthread...-Idle-Solution! (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.
http://forums.holley.com/showthread....neral-IAC-Info (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 Dropbox.com.
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 Log" folder (.dl file).
Someone will analyze/troubleshoot the problem & offer advice.
https://www.youtube.com/watch?v=iqHOtDNiTNA (How To Record & Email A Datalog)

Originally Posted by Danny Cabral
It's helpful to record a short datalog of an occurrence, Overlay it onto your Config File, and manually tune the lean or rich problem area.
Look at where the live cursor moves to during this occurrence, and manually tune (enrich or lean) that area of the Base Fuel Table.
When the engine is tuned & running well, you should decrease the Closed Loop & Learned Compensation Limits % to lock in a good tune.
https://www.youtube.com/watch?v=rHjLwJQ45Kw (Holley Sniper EFI Datalogging Tech Video)
http://forums.holley.com/showthread....7370#post47370 (Closed Loop & Learn Table - Especially posts #2, #6 & #11.)

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.

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).
http://documents.holley.com/techlibr...9r10543rev.pdf (Holley EFI Datalogger Instructions)
https://forums.holley.com/showthread...s-amp-Datalogs (Datalog Information - Read "NOTES")
https://www.youtube.com/watch?v=iqHO...C6FEA0BB99AF17 (How To Record & Email A Datalog)
https://forums.holley.com/showthread...7531#post77531 (Closed Loop Datalog Tuning - Posts #2, #4 & #6)

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