Haltech Nexus R3 VCU & Lexus GS300 | Lexus IS300 & more 1998-2001 Plug 'n' Play Adapter Harness Kit (HT-651379)

The GS300 2JZ-GE is the inline-six platform everyone knows, and standalone ECU support for the GS300 chassis is a natural extension of that.

The Lexus GS300 2JZ-GE platform has a strong tuning community, and standalone ECU support opens what the factory management keeps locked down. The Tuned By Shawn PNP Wiring Harness Kit for the Haltech Nexus connects directly to your factory harness without any permanent modifications, giving the Haltech Nexus full standalone engine control. No cutting, no splicing, fully reversible.

Advantages

• Power delivery that's smooth and consistent across the full torque curve
• Fuel and ignition timing calibrated to your actual modifications, not Toyota's conservative baseline
• Idle stability that's locked in regardless of temperature
• Consistent engine behavior across temperature ranges
• A proper tuning foundation for this specific chassis

Features

• Plug-and-play fitment for 1998-2001 Lexus GS300 2JZ-GE, all transmission types
• Compatible with Haltech Nexus R3, R5, S2, and S3 ECUs
• No cutting or splicing of factory wiring
• OEM-quality connectors, USA-built by Boomslang Fabrication
• Fully reversible, factory harness preserved
• For competition and off-road use

The Details

Built specifically for this vehicle's connector layout with OEM-spec connectors and correct wire gauge throughout. Your factory harness stays completely untouched and the vehicle can return to stock at any time. In automatic transmission applications, the factory ECU remains in parallel for transmission control while the Haltech Nexus manages the engine.

Kit Includes

• 1x Boomslang PNP wiring harness for 1998-2001 Lexus GS300 2JZ-GE
• Haltech Nexus R3 VCU
• Air Temp Sensor - Small Thread Thread: M14 x 1.5

Fitment

1998-2001 Lexus GS300 / 1998-2001 Lexus IS300 / 1998-2001 Lexus SC300 / 1998-2001 Toyota Aristo 2JZ-GE VVT-i / 1998-2001 Toyota Supra 2JZ-GE, All Transmission Types.