aRacer AF2 Professional Wideband AFR Module

The aRacer AF2 Professional Wideband AFR Module is the piece that makes real tuning possible. It's aRacer's improved wideband O2 module — a big upgrade over the older AF1 — and it now comes included with a Bosch LSU 4.9 wideband oxygen sensor for stable, accurate, fast AFR readings you can actually trust.

The headline upgrade is simplicity. aRacer redesigned the harness so the AF2 plugs directly into your aRacer ECU with no splitter, adapter, or extra cables — everything the old AF1 needed. That means a cleaner, faster install with no unused connectors or lengthy splitter wires to tuck away. Plug it in and get back to riding.

Paired with a compatible aRacer ECU, the AF2 unlocks autotune and enables Closed Loop Fuel Compensation on Stage 2 and higher setups, so your engine can correct its own air/fuel on the fly. It'll also run as a standalone wideband when paired with an aRacer multi-function display (DG-2) or the aRacer app. No calibration needed — high accuracy, high-speed response, right out of the box.

If you're running an aRacer RC MIni 5 ECU and want to tune it right, this is the module that gets you there.

Key Features:

• Includes a Bosch LSU 4.9 18mm wideband O2 sensor
• Stable, accurate, fast AFR readings — major upgrade over the AF1
• Plugs directly into the aRacer ECU — no splitter or extra cables needed
• Unlocks autotune + Closed Loop Fuel Compensation (Stage 2+ ECUs)
• Doubles as a standalone wideband with a DG-2 display or the aRacer app
• No calibration required — plug and play, high-speed response

NOTES: Required M18 Oxygen Sensor Bung on exhaust.  See Weld-On Oxygen Sensor Bung