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5VZ-FE Conversion Complete Engine Wiring Harness

5VZ-FE Conversion Wiring Harness
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Our Price: $1,499.99 - $1749.99

Product Code: 571503

Recipient Type*:

Transmission Type*:

7th Injector Add-on*:



It is important to read full product description before ordering:

The 5VZ-FE (3.4L) fuel injection system is entirely different from that of the older Toyotas. This means the 5VZ-FE (5VZ) electronics and circuit will have to be installed in your older vehicle in order to make this engine swap possible, Our 5VZ Conversion Wiring Harness will provide the donor vehicle engine and transmission control circuits in your older vehicle for use with the Toyota engine 5VZ computer and components.

From the factory, there are 2 primary parts of the OEM 5VZ fuel injection wiring circuit. The first is the engine wiring harness. This is the harness that is primarily attached to the engine. This is sometimes called the injector harness. This harness connects the engine components such as the fuel injectors, ignition coils, air flow meter, etc. to the engine computer (ECU) and the body harness.

The second part of the 5VZ electronic fuel injection circuit is built into the body wiring, along with the rest of the vehicle’s circuits. The body wiring includes the “under-dash” harness, the engine-bay harness (including fuse box), and even the wiring to the rear. About 40% of the 5VZ fuel injection’s wiring circuit is contained in this harness.

  • Our 5VZ Conversion Engine Wire Harness completely replaces the engine wire harness while also providing the portion of donor engine circuit originally in the body wiring. This harness is a combination of an engine wire harness and an adapter harness and houses 100% of the 5VZ 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 since the JDM engine wiring is hard to use in a LHD application.

We also accommodate 2 main recipient vehicle types:

  • Our 22R-E/3VZ-E Vehicle option is for ’85-’95 Truck/4Runner and ’93-’94 T100 vehicles that originally had the 3.0L 3VZ-E engine or the fuel injected 22R-E. This version requires that the original body wiring and fuse box is still in place and will plug directly into the body wiring for a simple install. Very little splicing is required to install this version; it is nearly 100% plug-and-play. The original wiring in your older Toyota will not have to be torn apart, and this version will accommodate your OEM gauges (tachometer will require some additional work during the install), speed sensor, reverse lights, 4×4 system and 4×4 indicator lamp.
  • Our Stand-Alone version is designed for virtually any other vehicle. It works well with carbureted vehicles, other makes, and some race/custom vehicles. This version requires that the vehicle has at least a basic electrical system already in place. This basic system must include: start and ignition switch, charging, fuse/battery and gauge circuits. This will connect to the recipient vehicle through a few simple splices. Note that the Stand-Alone version includes a fuel pump power/control circuit. Note: if your vehicle has no wiring body wiring at all see our Monster Harness.

We offer 2 options regarding the transmission:

  • Manual Transmission: Use this option when using a manual transmission. This includes a case where the donor or recipient vehicle was originally 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.

If using an original 3VZ-based A340 automatic transmission: the wire harness will connect directly to the A340 sub-harness and connections, however, some recipient models will require the use of a late-3VZ (94-95) or 5VZ-donor park/neutral switch (which is a simple and direct install).

7th Injector Add-on
If there are plans to use the URD 7th-Injector Fuel-Upgrade kit w/ a TRD/Magnuson Supercharger this add-on would be a big help. The 7th Injector has a small sub-harness that requires several splice-connections into the engine wiring. This can be difficult to trace wires and make the connections and requires cutting into an engine harness. Our add-on is a simple connection into our engine harness for the 7th Injector sub-harness. These required 7th Injector splice-connections are built into the new wiring and routed to an additional connector. This would allow you to take the additional provided pigtail, splice to the 7th Injector harness on the bench and simply plug it into our harness. This eliminates wire tracing and splicing into our new engine wiring. This upgrade also comes w/ a separate “lock-out” plug that allows our harness to be operated, in the meantime, without the 7th injector kit installed.

This product is built per order, please allow 4-6 weeks for order completion. This time can vary by season, if completion time is crucial, please contact us before ordering.

Notice when ordering: Please include the following information in the “Order Notes” box or a separate email when placing your order. If sending a separate email be sure the name on the order will be obvious.

From Donor Vehicle:

  • VIN, only if 100% certain of engine origin, OR part numbers requested below
  • Toyota ECU part number (8966x-xxxxx)
  • For Adapter Harness version: Toyota engine harness part number (82121-xxxxx), this is found on a paper tag near the ECU connections.
  • Model Year
  • Model
  • 4WD or 2WD
  • Manual or Automatic Transmission

From Your Vehicle:

  • For 3VZ-E/22R-E type: VIN – please email image of VIN tag with 1990 and older models
  • Year Model
  • Model
  • Original Engine
  • Manual or Automatic Transmission (originally)
  • Indicate specific transmission to be used in conversion
  • Shifter to be used (for A/T models)
  • 4WD or 2WD
  • If 4×4, indicate transfer case application, original to transmission or changed
  • Front suspension type (original or modified)
  • For 89-95 Truck, 90-95 4Runner, Indicate if ADD (Auto-Hub) system is in use
  • Swapped battery location
  • .OEM (original-type) tachometer in use?
  • Plans to add a supercharger with 7th-Injector fuel kit?
  • For Stand-Alone: ECU Location
  • For Stand-Alone: Fuel pump location
  • For Stand-Alone: speedometer type

Core Connectors for 22R-E/3VZ-E recipient type:
For some applications we will need a core connector from your vehicle. If your vehicle is an ’85-’90, we need one core connector. It is found on the 22R-E or 3VZ-E ENGINE harness, near the ECU connectors. There are the 2 connectors that join the engine harness to the body/dash harness, one of these is needed. Once an order is placed, we will send a picture of the connector needed and a label file (for print) that can be used to send the core connector in a USPS Small Flat Rate Box. Cut the connector needed from the ENGINE harness w/ 1-3″ of wire lead. Note: we will fill the core connector w/ new wire terminals.