UZ Conversion Wire Harness (Choose Options)*

***It is important to read the full product description before ordering.***

This product is built to your specifications, so please allow 6-8 weeks for order completion. This product is NON-REFUNDABLE once all wire harness details are collected and production has begun. We will confirm via email before production begins.

If completion time is crucial, please contact sales@northwesttoysllc.com before placing your order.

what it is:

The UZ-FE Conversion Wiring Harness is the proven, high-quality wiring solution developed by North West Toys (NWT) and Off-Road Solutions (ORS) for Lexus Toyota UZ-FE (4.0L V8) engine swaps into older Toyota platforms and custom builds.

Whether you’re restoring a workhorse, building a trail rig, or doing a clean daily-driver swap, this harness integrates the complete factory engine and transmission control circuits into your recipient vehicle, preserving OEM functionality while making installation as close to plug-and-play as possible.

why you need it for your UZ swap?

The UZ-FE fuel injection and ignition systems are entirely different from those of earlier Toyota engines, meaning a complete and accurate wiring circuit is required for the swap. Factory UZ wiring is split between:

The engine wiring harness attaches to the engine and connects components, such as injectors, ignition coils, and the airflow meter, to the ECU and body harness.

The body wiring harness is located under the dash and throughout the vehicle, containing ~40% of the EFI circuit.

Without a proper conversion harness, completing this circuit requires hours of custom splicing. This ORS x NWT harness eliminates that hassle, ensuring reliable connections, correct sensor inputs, and proper ECU communication.

Step 1: utilize the drop-down list to provide details about your swap.

• Format
• Donor
• Recipient
• Transmission

Format:

Adapter Harness Format
Our Adapter Harness is designed for applications that have a used, good-condition, fully intact engine wire harness from the donor vehicle. Our Conversion Adapter Harness connects directly to the engine wire harness and the ECU, working in conjunction with the donor engine wire harness to complete the engine wiring circuit. Note: The Adapter Format of our conversion harness will not work with “JDM” engine wiring (from the Japanese Domestic Market).  Our Engine wiring format is recommended for use with JDM donor engines. 

Engine Harness Format
Our Engine Harness completely replaces the engine wire harness, while also providing the portion of the donor engine circuit that was originally part of the body wiring. This harness is a combination of an engine wire harness and an adapter harness, housing 100% of the UZ engine circuit in one all-new piece. It is intended for situations when the donor engine wiring is missing, cut, or in poor condition, or when all-new wiring is desired. It also works well for JDM import engines, as the JDM engine wiring is hard to use in a swap application. Note: The UZ Engine Format will include both the knock sensor and front-engine sub-wiring harnesses, all new.

Donor:

• 1UZ (1990-1997)
• 1UZ (1998-2000)
• 2UZ
• 3UZ

Recipient:

• Pickup (1985-1995)
• 4Runner (1985-1995)
• 4Runner (1996-2002)
• Tacoma (1995-2004)
• Tacoma (2005-2015)
• Other 

Transmission:

Manual Transmission
Use this option when using a manual transmission. This includes a case where the donor or recipient vehicle was originally an auto, and the engine setup will now be manual.

Automatic Transmission
Use this option when using a Toyota automatic transmission. This includes a case where the recipient was originally manual but is now being converted to an automatic transmission. Like the engine circuit, the transmission control circuit was originally split between the body and engine wiring. The Adapter format will include the portion of the transmission control circuit originally placed in the body wiring, and the Engine Wire Harness format will include all-new transmission connections. Note:The UZ Conversion Wiring is designed for use with the donor automatic transmission. For use of an Automatic Transmission from a different application (including the recipient), inquire with sales@northwesttoysllc.com regarding compatibility.

Optional Add-ons:

EGR Delete
The 90-97 UZ Engine Control System utilized an EGR system to meet emissions requirements. In off-road vehicles where the EGR system has been removed, a resistor set or a small bypass connector can be added to help eliminate the associated Diagnostic Trouble Codes.

A/T > M/T Resistor Set
When using a Manual Transmission with a 95 or newer UZ Donor Engine, Diagnostic Trouble Codes (DTCs) will be continually present due to the absence of the donor automatic transmission. This will leave the engine light constantly ON. To avoid these codes, we offer a Resistor Set that connects to the engine wiring and simulates the missing transmission components, helping to prevent these trouble codes. Note that in some cases, this will also require the customer to purchase a separate device for speed signal calibration from an outside source.

Battery Cable Set
When using the Engine Conversion Harness, battery cables can be added. These are separate cables, designed for length and routing to fit 1979-1995 Truck and 4Runner recipients, with the battery in either front corner of the engine bay. These cables will include new military-style battery terminals.

Order Notes

Please include the following information in the “Order Notes” box or a separate email to sales@northwesttoysllc.com when placing your order. If you are sending a separate email, please ensure that your name and order number are included. 

From Donor Vehicle:

• VIN, only if 100% certain of engine origin

OR part numbers requested below:

• Toyota ECU part number (8966x-xxxxx)
• Adapter Harness (82121-xxxxx) can be found on a paper tag near the ECU connections.
• Year
• Model
• 4WD or 2WD
• Manual or Automatic Transmission
• Will the EGR system be used or deleted?

From Recipient Vehicle:

• For 3VZ-E/22R-E type: VIN 
• RH Drive or LH Drive
• Year 
• Model
• Original Engine
• Original Transmission Manual or Automatic
• Indicate the specific transmission to be used in the conversion
• Shifter to be used (for A/T models)
• 4WD or 2WD
• If 4x4, indicate transfer case application (original or modified.
• Front suspension type (original or modified)
  
• Swapped battery location
• OEM (original-type) tachometer in use?
• Cruise Control in use?
• Is the oil pressure gauge or light in use?

For "OTHER" Recipients:

• Fuel pump type and location
• ECU location
• Speedometer type

For "1985-1995 Truck/4Runner" Recipients:

• Indicate if the ADD (Auto-Hub) system is in use