This wiring harness interfaces a Holley EFI ECU to a 1999-2004 2-Valve Ford Modular engine, using most stock sensors and pairing with an injector harness, coil harness, and ignition modules.
Specifications:
- Harness Application: Ford
- Ignition Type: 2V Ford Modular
- Injector Connector: Jetronic/Minitimer (Bosch)
- Includes: Main Power Harness, Ford Modular Main Harness, Ford V8 Injector Harness, Ford Modular 2V Coil Harness, Coil Drivers
- Product Type: Harness Kit
- Part Number: 558-505
This kit is meant to be used in conjunction with an injector harness, coil harness, and ignition modules. You'll need to purchase an ECU and O2 sensor separately to complete the kit.
Compliance: This part is legal for sale and use on Racing Use Only Vehicles — competition vehicles that are not registered and never operated on the street. It is against the law to install this part on an Emissions Controlled Vehicle (1966-and-newer California-certified or 1968-and-newer federally certified vehicles).
FAQ
What years/engines does the 558-505 harness kit fit?
1999-2004 Ford Modular 2-Valve engines.
Does it include an ECU or oxygen sensor?
No, you'll need to add a compatible ECU and O2 sensor separately.
What else do I need to complete the installation?
An injector harness, coil harness, and ignition modules.
What's included in the kit?
Main power harness, Ford Modular main harness, Ford V8 injector harness, Ford Modular 2V coil harness, and coil drivers.

