22R Fuel Injection Conversion Harness (ORS-EC002)

Fuel Injection Conversion Harness

’85-’88 Minitruck & ’85-’89 4Runner Donor Fuel Injection

*****NOTICE TO CUSTOMER: If there is a problem suspected with the wiring harness, call ORS. DO NOT cut, alter, or dissect the ORS conversion harness. Off Road Solutions accepts no responsibility for a harness that has been tampered with – NO EXCETPIONS.

There are cores needed when performaing this swap to build your harness: List of Cores Needed

Following is a list of parts needed for the ORS fuel injection conversion on a 22R engine. These parts must be used in conjunction with the ORS wiring harness to complete your conversion. These parts must be removed from a 1985-1988 pickup or a 1985-1989 4Runner equipped with a 22RE engine. We highly recommend that all these parts are removed from the same vehicle.

  • Intake manifold *
  • Intake plenum and throttle body assembly *
  • Exhaust manifold with oxygen sensor fitting (optional) *
  • Exhaust manifold gasket
  • Intake manifold gasket
  • VSV/fuel pressure up *
  • VSV/evaporative (optional) *
  • VSV/EGR (optional) *
  • Fuel filter *
  • Fuel filter bracket *
  • 2 high pressure fuel hoses *
  • Fuel line from fuel tank
  • High pressure fuel pump
  • Fuel rail *
  • 4 fuel injectors w/ o-rings *
  • Fuel pressure regulator *
  • Fuel dampener *
  • Fuel line gaskets
  • Knock sensor *
  • Power steering pump with vacuum valve *
  • Air filter box
  • Intake hoses
  • Air flow meter
  • Passenger side water pipe from timing cover *
  • Throttle body coolant hoses *
  • Distributor *
  • Plugs, wires, cap and rotor * (different than carbureted)
  • Engine wiring harness *
  • ECU
  • Circuit opening relay
  • Oxygen sensor
  • Power steering reservoir (optional)
  • PCV hoses *
  • Assorted vacuum hoses (optional) *
  • Vacuum hose rail *
  • EGR pipe *
  • Upper radiator hose *
  • Injector resistor (P/S inner fender)

* indicates items attached to engine

Following is a list of parts that we recommend replacing when doing this conversion. These parts are available through ORS or a local parts store.

  • Exhaust manifold gasket
  • Intake manifold gasket
  • Fuel filter
  • 2 high pressure fuel hoses
  • Injector o-rings
  • Fuel line gaskets
  • Throttle body coolant hoses
  • Plugs, wires, cap and rotor (different than carbureted)
  • Any PCV or vacuum hoses in poor shape
  • Circuit opening relay
  • Any radiator hose or drivebelts in poor shape

The ORS fuel injection conversion harness is installed after all conversion parts are installed on the vehicle.

Read all instructions before beginning installation.

There is a supplement for ’79-’84 Toyota carbureted Trucks/4Runners that will modify the installation slightly.

  1. Be sure that the engine ECU is properly mounted and the engine wiring harness is routed and connected to the ECU. Connect the 2 large yellow connectors on the ORS conversion harness to the matching plugs on the engine harness near the ECU. Connect the remaining yellow connector to the ECU.
  2. Securely mount the relays in a safe location.
  3. Route the harness lead containing the check engine light toward the driver side of the vehicle. Mount the check engine light.
  4. Connect the “12V ignition on” lead to a switched power source that provides 12V only when the key or ignition switch is on.
  5. Connect the brake light switch signal to the switching side of the brake light circuit. This is the side provides 12V only when the brake pedal is depressed. The brake signal is not required but recommended.
  6. Connect the “12V start signal” lead to a switched power source that provides 12V only when the key is in the start position or the start button is depressed.
  7. Connect the “oil pressure”, “H2O temp”, and “tachometer” leads to the sender wires of the appropriate gauges.
  8. Connect the speed sensor lead to a 1-wire speed sensor signal. This will be the wire that powers the speed sensor into the speedometer. The speed sensor signal is not required but recommended.
  9. Connect the ground lead to a good chassis ground.
  10. Route the lead containing the “to battery” fuse-holders to the battery positive terminal. Remove the fuses. Connect the lead to the battery positive terminal.
  11. Connect the “injector resistor” terminal to the injector resistor. This is the aluminum resistor on the passenger-side fender-well.
  12. Route the fuel pump leads to the fuel pump. Connect the positive and negative leads. Do not connect backwards.
  13. Route the remaining leads to the driver side fender area. Connect to the “air flow meter” lead to the air flow meter.
  14. Connect the “oxygen sensor” lead to the oxygen sensor.
  15. Connect the “ignition coil” lead to the 2 wire connector on the ignition coil.
  16. The remaining yellow connectors and the “O2 check connector” (if applicable) are for diagnosis of the EFI system. Place electrical tape over the face of these connectors and secure them to the harness using wire ties.
  17. Be sure that all connections are secure and all wires are routed properly and securely. Be sure that wires are not in danger of heat, exhaust, or sharp edges.
  18. Install the 3 fuses in their respective fuse holders.
  19. The wiring part of your conversion is complete!




  • Locate the original Emissions Control Computer in your vehicle. This is normally in the passenger side kick-panel. Disconnect and discard this computer.
  • Locate the following wires in the connector to the Emission Control Computer. Cut the wire from the connector and directly splice to the wire lead in the ORS harness according to the chart below.
    Emission Control Computer Wire Color To ORS Harness Lead
    -Green w/ blue stripe To + speed sensor signal
    -Black To tachometer



When Using An Internally Regulated Alternator In An Externally Regulated System

  • Locate the wiring harness that connects to the newer alternator. This will be the battery harness on 5VZ and 3RZ applications. On 22R-E applications this harness will be a separate piece about 18″ long, directly connected to the alternator. Connect this harness to the alternator and route this harness (if necessary) to the driver side fender-well area.
  • Find the original external alternator voltage regulator (IC Regulator) on the driver side inner fender-well area. Remove the regulator. The following steps refer to the remaining regulator connector.
  • Cut the appropriate wires from the original IC Regulator connector and splice the wires according to this chart:
    Original IC Regulator Connector To Newer Alternator Wiring
    -Smaller white wire To Smaller white wire
    -Red wire To Red wire
    -Yellow wire To Yellow wire
    -Large white cable To Large white cable



Locate the wiring harness that connects to the newer alternator. This will be the battery harness on 5VZ and 3RZ applications. On 22R-E applications this harness will be a separate piece about 18″ long, directly connected to the alternator. Connect this harness to the alternator.

The following will satisfy the alternator wiring:

  • Red wire: “ignition on” 12V power – 12V when the ignition s/w is activated, fused at 10A – don’t give this constant power
  • Small white wire: 12V battery power, direct connection to battery + terminal, fused at 7.5-10A.
  • Yellow wire: ground signal for “charge warning lamp”. This provides a ground signal for a lamp in case of alternator failure.
  • Large white cable: main alternator cable. This should be connected to the battery + terminal with an 80-100A fuse or fusible link in between.


  • Les Moore says:

    Just got parts for 22r to 22re conversion guy i got from hacked harness. How much for your harness and do i need og 22re harness?

    • Mike Caskey says:

      In addition to our Stand-alone Conversion Wiring Harness, you will also need a good (intact) engine wire harness. At this time you will need to find a good-condition used harness. ORS hopes to offer an all-new replacement engine harness for this engine and a few other by the end of 2016.

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