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HAR-HOLLEY

Tools Required for Installation:

  1. Terminal Crimping Tool
  2. Wire Strippers
  3. Electric Drill
  4. 2" Hole saw (for the rubber grommet in the firewall)

    5. CAUTION: BEFORE BEGINNING INSTALLATION, DISCONNECT THE POWER FROM YOUR VEHICLE BY REMOVING THE NEGATIVE BATTERY CABLE FROM THE BATTERY.

1. PCM/Fuse block mounting:

    PSI harnesses are generally designed to place the computer and fuse block under the passenger side of the dash or kick panel, however anywhere under the dash should work as well. Some applications may allow the computer to reach under the seat, and others have left the computer and fuse block in the engine bay. Make sure water and road debris will not come in direct contact with them. A good exercise is to lay out the wire harness on the floor beside your vehicle and identify all the connectors and wires. Allow enough slack in the harness at places where movement could possibly occur (body to frame, frame to engine, etc.).

    2. Grounding:

      As with all automotive wiring, the grounding circuit is critical for proper operation. Ensure that there is secure grounding of the following, battery to engine, battery to chassis, engine to chassis, harness to engine, and harness to chassis. A ground strap kit KIT-1025 is available from PSI.

      NOTE: This harness is equipped with Ground Wiring on the rear portion of the driver side cylinder head.

      2a. Connect a ground strap/cable (minimum of a 4 Ga. wire) from the negative battery terminal to the block.

      2b. Connect a ground strap (minimum of a 4 Ga. wire) from the engine to the chassis (frame).

      2c. Connect a ground strap from the engine to the body/firewall.

      ENSURE ALL GROUND LOCATIONS ARE CLEANED OF PAINT, GREASE, OIL OR OTHER CONTAMINANTS

      3. Mark the position where the wiring harness will come through the firewall with a metal punch. Using a 2” hole saw, drill a hole in the firewall. Make sure to debur the hole with a file.

      4. From inside the vehicle, feed the Engine Section of the wiring harness through the 2” hole. Push the grommet (already installed on the harness) into the hole until it is seated.

      5. Route the engine compartment section to the top of the engine. The engine section is designed to be separated into left side (driver) and right side (passenger) sections. The driver side of the engine section has the connectors for coolant temp, alternator, and the IAT sensor. Reference the Harness Layout diagram.

      5a. Connect the black ground ring terminal to the back of the cylinder head.

      6. ECU Connectors:
      J1A - The first connector next to the USB connector is the “J1A” connector (34 pin). This connector is primarily an “Input” connector. It contains all the sensor inputs and wide band oxygen sensor control.
      J1B - The second connector is the “J1B” connector (26 pin). This connector is the “output” connector. It has 8 injector outputs and outputs for other devices.
      J3 – Connection point for the Drive-By-Wire harness (X Max Only).
      J4 – Connection point for the Transmission harness (X Max Only).

      Main Power: Install the main power and ground harness directly to the battery. The RED wire should go DIRECTLY to the positive post on the battery. The BLACK wire should go DIRECTLY to the negative post on the battery.
      Do not connect to the ECU until after ALL wiring and installation is performed.

      7. Gen III 24X vs Gen IV 58X Engine:
      This harness is designed to be used with either Gen III (24x) engines or Gen IV (58x) engines depending on how the harness was ordered. The 24x vs 58x crank sensor connector is keyed differently so it is specific to the engine.

          7a. 58X: If the harness was ordered for a Gen IV 58x engines, you will have an included cam sensor extension harness (EXT-1008) to reach the cam sensor on the front timing cover, as well as a knock sensor adapter harness (EXT-1020) to accommodate side mounted knock sensors.

      8. Starter Wiring:

      The PSI harness does not have a starter solenoid wire included. This wire would come directly from your key (ignition switch) and connect directly to the starter solenoid. This is usually a purple wire for most GM vehicles. The 2 red ring terminals on the PSI harness connect to the 12-volt battery terminal on the starter.

      9. Ignition Wire:
      A red Ignition Feed wire is coiled up at the fuse block. This wire must be connected to a power source on the vehicles fuse block that provided 12V Key on AND Cranking Power. A common source is the “ACC” location on a GM fuse block or a distributor coil wire.

      10. Fuel Pump Wiring:
      A fuel pump relay is provided with the signal side of the relay being pre-wired from PSI. The fuel pump power wire is not provided as length and wire size may vary. The power wire must be pinned into the fuel pump relay using the supplied terminal and run directly to the positive side of the fuel pump. The relay is already fused by PSI using a 30amp fuse. This is adequate for most standard fuel pumps including all Walbro 255-450lph fuel pumps. For high horsepower applications where a larger fuel pump or dual/triple pump system is being used, you can use the PSI relay to trigger an independent fuel pump relay or fuel pump controller. Make sure to properly ground your fuel pump.

      11. Oxygen Sensor:
      The oxygen sensor should be mounted at a point where it can read a good average of all the cylinders on one bank. This would be slightly after all the cylinders merge. Do NOT mount the sensor far back in the exhaust as this will negatively impact closed loop operation response. If you have long tube headers, mount the sensor approximately 1-10” after the collector. You must have no less than 18 – 24” of exhaust pipe after the sensor. Only one o2 sensor is used for Holley Systems.

      12. Inputs & Outputs:
      Terminator X base calibrations from the wizard in the handheld are pre-configured with 3 outputs and 1 input to be used for the following features:

      • Fan #1 output: Position E (Yellow) (Ground trigger for relay)
      • Fan #2 output: Position F (Gray) (Ground trigger for relay)- Fan #1 output: Position E (Yellow) (Ground trigger for relay)
      • A/C Shutdown: Position G (Light Blue) (Ground trigger for relay)
      • A/C Kick input: Position A (Dark Blue) (Ground)

      A/C Shutdown – This output will provide a ground output at a defined throttle position. If desired, this throttle position can be changed using the software. This output can be used to trigger a relay that deactivates the A/C at higher throttle positions. This may require the installation of a 5-pole relay in the existing A/C wiring.

      A/C Kick input – This ground input will allow for the IAC motor to automatically make an increase in IAC %, which is necessary to avoid a momentary drop in idle speed when the A/C compressor turns on.

      13. Automatic Transmission Control (4L60/65/70e and 4L80e):

      4L60e and 4L80e control is only available when using a Terminator X MAX ECU. The automatic transmission harness will plug into the J4 ECU connector on one end, and directly to the transmission on the other.

      • VSS (vehicle speed sensor): The VSS is located on the rear driver side on a 4L80e and the rear passenger side on a 4L60e.
      • ISS (input speed sensor): ISS is only required when using a 4L80e.
      • Power and Ground: The transmission harness will have a 12v constant power supply wire and a ground wire with ring terminals pre-installed. The pink wire on the fuse block will need a 12v switched ignition source. CAUTION: The pink wire MUST be a different source than the ECU ignition source!
      • Brake Switch: The loose purple wire must go to a brake switch. This wire needs a +12v signal when brakes are applied. This will unlock the torque converter when the brakes are pressed.

      14. Throttle body and Accelerator Pedal: 

      Drive By Cable (DBC): If the harness was ordered for DBC, you will have a TPS (throttle position sensor) and IAC (idle air control) plugs on the front passenger side injector harness. These will plug into any GM or aftermarket cable throttle body.

      Drive By Wire (DBW): Drive by wire is only available when using a Terminator X MAX ECU. If ordered for DBW, the harness will have a 6 wire LS3 style throttle body plug included on the front of the passenger side of the harness. The harness will also include an accelerator pedal harness. The pedal harness will plug into the J3 ECU connector and will have a connector for a C6 Corvette (2005-13) accelerator pedal (PSI part# ACC-1007).

      • Brake Switch Wire: The loose red wire coming from the DBW pedal connector (J3) must be connected to a +12v input from the brake pedal switch.

      Holley designed the drive-by-wire system to utilize a brake pedal switch input. This is wired to a +12v input from the brake pedal switch. If the brake pedal is depressed enough to activate the brake light switch, the following occurs:

      • The ECU will not allow a throttle position over 10%, no matter how far the pedal is pushed. This consequently limits the opening of the throttle body. Fuel flow will also be limited to 30lb/hr.

      WARNING: Installation of this safety circuit is required when using the drive-by-wire feature! Defeating or neglecting to install this input is done so at the users’ own risk. The user assumes any and all liability for any damage, as a result of a drive-by-wire malfunction.

      CAUTION: Do NOT cut, shorten, lengthen, or modify any DBW components for any reason! Do NOT run the DBW harness components directly past any high voltage or “noisy” sources.

      15. Final ECU Connection:
      If ALL other wiring and connections have been made, connect the main power harness to the ECM
      CAUTION: BE SURE THE IGNITION IS OFF WHEN YOU RECONNECT THE BATTERY OR DAMAGE TO THE PCM MAY OCCUR!

      16. Initial Power-up:
      At this point, the installation of your EFI system should be 100 percent complete. The ECU, TERMINATOR X Handheld controller, throttle body and intake hardware, all sensors, wiring, fuel pump, regulator and return line, and all other hardware should be installed. It is now time to use the Handheld controller to write a base calibration into the ECU for initial startup! All Holley ECUs are shipped without any tune present. A base calibration must be written before you can attempt to start the engine.