Browser-based EFI diagnostics
Road-tune your Holley Sniper EFI in a browser.
No dyno, no drivers, no install.
Tuneless reads live data from your Holley Sniper ECU over WebUSB, flags calibration issues in plain English, and walks you through safe, user-approved corrections from a Chrome tab.
Chrome / Edge · WebUSB · No install · No drivers
Designed for supported street-driveability workflows. Professional or dyno validation may still be appropriate.
The install is only the start
It runs.
It doesn’t run right.
Fuel pressure set, sensors baselined, harness routed. The hardware is done — and the calibration is still whatever shipped in the box.
Illustrative pre-flight checks
Existing tuning software means installed desktop apps, Java version conflicts, and comm-port driver headaches. Tuneless runs in a browser tab. Plug in the adapter, open Chrome, and you are reading live data.
Connect. Verify.
Know what it sees.
A USB-CAN adapter and a browser tab. Tuneless reads the live sensor stream straight from the ECU and puts it in front of you labelled — not as raw hex, and not buried three menus deep.
Cruise cells are stable. Verify warm restart next.
Ask Jules
Ask Jules about engine behaviour — “stalls when warm” gets you a fix, not a forum rabbit hole.
Jules is Tuneless’s AI tuner. Ask what a symptom means, why a proposed correction looks the way it does, or what to check before you drive.
Symptom search
Type what the engine is doing — “stalls when warm,” “bogs on throttle” — and get the suspected cause and fix.
Plain-English diagnostics: symptom in, cause and correction out — not a table to hunt through.
The data gets a
second opinion.
Warm idle is outside the reliable learning band for this cam profile.
Hold idle steady. Verify oxygen-sensor behaviour before applying any change.
Rollback is an additional safeguard; it may not detect or prevent every unsafe condition.
Illustrative product UI · you approve every change
05 Apply
Starts clean. Idles smooth.
Pulls like it should.
Changes are bracketed by a snapshot and read back from the ECU to confirm what landed. Snapshots may support rollback, but they cannot prevent every fault or form of damage — keep an independent known-good backup of your own.
Ready when the build is
Tune with confidence.
Then go drive.
Guided road tune · Plain-English diagnostics · Snapshot + rollback
Current compatibility
Exact configurations, not a badge.
Holley Sniper 1 · Holley Sniper 2 EFI
Only for the listed ECU, firmware, adapter, browser and vehicle configurations. See the Compatibility Guide for the tested matrix and known limitations.
Holley Terminator X
On the roadmap. Read-only today; write support not yet available.
Tuneless is an independent third-party software product. It is not affiliated with, sponsored by, endorsed by, or approved by Holley Performance Products Inc. Tuneless uses the names Holley, Sniper, Terminator and Dominator solely to identify relevant third-party ECU products. These names are trademarks of their respective owners.