Electrical Connections; Air Charge Temperature Sensor; Coolant Temperature Sensor; Throttle Position Sensor (Tps) - Holley MPI PRO-JECTION Installation Tuning And Troubleshooting Manual

4 - Slit the 2" grommet provided and position around the wiring harness. Slip the grommet into the 2" hole to prevent the
wiring harness from chaffing. A light application of WD-40 on the grommet will ease the installation.
5 - Connect the wiring harness to the ECU. Push the plug into the ECU until the lock snaps into position.

11.0 ELECTRICAL CONNECTIONS

An electrical diagram is provided for reference during connection of electrical components. This diagram shows the connectors
included with the wiring harness and table shows the color codes and connections for all of the loose wires without connectors.
See page 32 for the wiring harness diagram.
LOOSE WIRE COLOR AND DESCRIPTION
Black
Red with fuse
Red/White
Yellow
Orange/Red
Yellow/Black
WARNING! Keep all wires away from hot exhaust components. Bare or frayed wires can result in electrical short
circuits which can cause system or vehicle damage, or a fire hazard resulting in property damage,
serious injury and/or death.

11.1 Air Charge Temperature Sensor

Locate the 2 wire flat connector with BLUE and BLACK/WHITE wires. This is the wire set that is bundled with the injector
connector. Plug this connector into the air charge temperature sensor on the throttle body.

11.2 Coolant Temperature Sensor

Locate the 2 wire flat connector with BROWN and BLACK/WHITE wires. Plug this connector into the coolant temperature
sensor mounted earlier.
11.3 Throttle Position Sensor
Locate the 3 wire flat connector with BLACK/WHITE, GREEN, and ORANGE wires. Plug this connector into the throttle position
sensor located on the throttle body.

11.4 Idle Air Control (IAC) Motor

Locate the 4 wire flat connector with the PURPLE wires. Plug this connector into the mating connector on the throttle body.

11.5 Injectors

Locate two bundles with four square injector connectors in each. One bundle will contain four connectors with RED and WHITE
wires and the other will contain four connectors with RED and BLUE wires. These wires should be routed underneath the
independent runners of the manifold. One bundle should connect to the injectors on the right side of the engine and the other
bundle should connect to the injectors on the left side of the engine. Plug the connectors into the female mating connector of the
injectors.

11.6 Manifold Absolute Pressure (MAP) Sensor

Locate the 3 wire flat connector with the following color wires: BLACK/WHITE, ORANGE, AND RED/BLACK. Plug this
connector into the MAP sensor.

11.7 Oxygen Sensor

Locate the 3 wire flat connector with RED, BLACK, and WHITE wires. Feed this harness to the exhaust manifold area where the
oxygen sensor is located. Plug the 3 wire flat connector into the mating connector on the oxygen sensor.
WIRE CONNECTION LOCATION
Ground connection
12 Volt - attach to t battery
Switched ignition wire, positive side of the coil
Ignition/tachometer wire, negative side of the coil - factory ignition only
Oil pressure switch wire
Ignition/tachometer wire, aftermarket ignition only
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