Air and Fuel› Carburetors and Components
Holley
EFI BENCHTOP TEST HARNESS FOR FIRMWARE UPDATING DASH CONFIGURATION AND ECU TESTI
SKU: H00E 558-127
Moderate — 2–4 hours
Description
Part #: 558-127
Designed for benchtop testing and setup of HP, Dominator, Terminator X, Terminator X Max, and Sniper ECU's, as well as 7" dashes.
Features:
- Terminated connectors for several EFI inputs
- Included power switch allows for a quick ΓÇ£install" on your test bench
- Great for ECU diagnostics that do not require a running engine, firmware updates, or 7" dash calibrations
Firmware Updating - Dash Configuration - ECU Testing
Fitment
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Available on iOS & Android
Specifications
| Brand | Holley |
| Part Number | H00E 558-127 |
| Weight | 0.92 lb |
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Buy with Confidence
Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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