Injector Wiring

High horsepower boosted cars often need large injectors. Most large capacity injectors are available in peak and hold form - about 2 ohms impedance, whereas most stock injectors from about 92 on are saturated (8-10 ohms impedance). Honda engine computers require a total injector impedance of about 10 ohms so a resistor pack is needed whenever the stock saturated injectors are swapped with peak and hold.

Early model injected Hondas; 90-95 Prelude and Accord; 89-91 JDM B16A Hondas all ran external resistor packs with low impedance injectors.

This wiring diagram shows the wiring for saturated (upper), and peak and hold injectors (lower). The engine computer activates the injectors by grounding each injector in turn.

Converting to Peak and Hold injectors

Near the brake master cylinder on OBD I cars is a connector that distributes power to the injectors and a number of sensors. Verify with a multimeter which wires go to the injectors. Cut all 4 and connect the wires coming from the injectors to the resistor pack. Connect the power wire from the resistor pack to all 4 of the unused wires coming from the power connector. OBD II cars may have this connector somewhere under the intake manifold.

12V power distribution connector

Connector showing injector pins

Resistor pack in place