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Holley EFI

Holley EFI Ford Foxbody Main Harness

Part # 558-128 Be the first to write a review

Plug and Play with fuel injected 5.0L Small Block Ford Engines

Holley EFI Ford Foxbody Main Harness

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Advertised Price $562.95
$505.95
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This harness is for fuel injected small block ford engines such as 5.0L or 5.8L Windsor powerplants. Plug and play ignition capability with Dual Sync and HyperSpark Distributors. The 5.0L Ford main harness is pre-terminated with Ford PWM IAC connector for the OEM PWM - idle air control motor commonly found on late 80's and early 90's engines. Compatible with Holley EFI Dominator, HP, and Terminator X and X Max ECU's.

Features:

  • Designed for use with fuel injected small block ford engines
  • Plug and play ignition capability with Dual Sync and HyperSpark distributors
  • Compatible with Holley EFI Dominator, HP, and Terminator X and X Max ECU’s
  • Comes pre-terminated with Ford PWM IAC connector for OEM PWM - idle air control motors
  • For OEM Ford fuel injectors, use injector harness 558-209
  • For TFI distributor applications, use ignition adapter 558-305

About Holley EFI

Find standalone EFI for LS, Coyote, Hemi and more at Holley.com. From engine swapping to managing up to 4000 horsepower, we have a solution for every project!

Brand Holley EFI
CategoryEngine
Emission Code4
Grade TypePerformance
Harness ApplicationFord
Harness TypeMain
Part TypeEngine Wiring Harness
Product Type5.0L Ford Main Harness
Sub CategoryWire, Cable and Related Components
Terminal TypePin
UPC090127074428
Part Number558-128
4

This part is legal for sale or use on Racing Use Only Vehicles

The following vehicles are considered Racing Use Only Vehicles:

  • Racing Use Only Vehicles are vehicles that are used exclusively for competition that are not registered and that may never be used on the street.

WARNING: It is against the law to install this part on an Emissions Controlled Vehicle

EFI selection chart
Instructions - 199r11957.pdf
Instructions - Wiring Diagram - 271R1252A.pdf
The following guide overviews all connections on the main harness. The main harness supports all the primary engine sensors, fuel and ignition for eight cylinder engines, the #1 wideband oxygen sensor, and the first four programmable input and output channels. There are two connectors for this harness designated as “J1A” (pin designations below that start with an A) and “J1B” (pin designations below that start with a B).
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Holley EFI
Ford Foxbody Main Harness
Plug and Play with fuel injected 5.0L Small Block Ford Engines
Part# 558-128
Advertised Price $0.00
$505.95
Save $57.00
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    Some parts are not legal for use in California or other states with similar regulations.

    Holley EFI Ford Foxbody Main Harness
    Holley EFI Ford Foxbody Main Harness
    Advertised Price $562.95
    $505.95
    Save $57.00