Lambda Optimizer Kit Yamaha Euro5+ 2024-

Lambda Optimizer Kit Yamaha Euro5+ (from 2024 onwards) – Eliminates check engine light and P0420 error

The Lambda Optimizer Kit is the new device developed for all Yamaha Euro5+ models (from 2024 onwards), compatible with models such as MT-09, MT-07, Tracer 700/900, XSR700/900.

The kit eliminates the annoying check engine light related to the second lambda sensor, especially the frequent reading errors (P0420 error code), and at the same time optimizes performance at low and mid revs, making power delivery smoother and more enjoyable in everyday riding.

The system communicates with the second lambda sensor, transmitting optimized parameters to the ECU, to always get the best out of the engine.

It has been designed for:
- riders who want to remove the catalytic converter for track use.
- riders who want to further optimize throttle response even with a catalyzed exhaust.
- riders who want to avoid false P0420 errors from the second lambda sensor, often caused by its extreme sensitivity (even to humidity after washing the bike).

Easy plug & play installation, no permanent modification required.

Installation Instructions

Step 1 – Locate the post-catalyst lambda sensor
Locate the second lambda sensor (the one after the catalytic converter) on the exhaust system. It is usually positioned on the header or on the pipe just after the catalytic converter.

Step 2 – Connect the device
1. Disconnect the electrical connector of the rear lambda sensor.
2. Connect the device in line between the lambda sensor and the original wiring harness of the bike.
3. Connect the ring terminal cable directly to the negative pole of the battery or to an engine screw.

Step 3 – Position the device
Install the module in a safe spot, away from excessive heat, vibrations, and moisture. Use zip ties to secure it firmly, making sure the cables are not under tension and do not interfere with moving parts.

Important note: if the check engine light is already on at the time of installation, it must be reset using an OBDII tool with a dedicated app (e.g. Torque) or with the official Yamaha diagnostic system.