4.0 Fuel Injector Wiring

[Rounder]

Does anybody know when you wire the fuel injectors, do you wire them in the firing order or by cylinder number?

 

[Curious Hound]

Somebody knows. But not me. It seems you need a diagram to attach each one by cylinder number to the proper pin at the ECU so that it can take care of the firing order.

 

[RonD]

Welcome to TRS

They are wired by cylinder number


Fuel injectors all get 12volts(key on) on a shared 12volt wire, just daisy chained from one injector to the next, usually a RED wire

Then, depending on the year, there will be either 2 Ground wires from computer(Batch fire injection) or 1 ground wire per injector from the computer(Sequential injection)

The computers pin's ID the firing order, you need a wiring diagram of computer pins for the YEAR and engine, it will also have the wire colors used that year for each injector

So what YEAR is the 4.0l Ranger?

And we can post pins and colors

Example 1997 4.0l
Injector wire by cylinder:
#1 pin 75 Tan
#2 pin 101 White
#3 pin 74 Brown/yellow
#4 pin 100 Brown/blue
#5 pin 73 Tan/black
#6 pin 99 Green/orange

Ford Computer pin numbers are laid out like this: https://www.grandmarq.net/oldfuelinjection/images/eec05.gif

The computer is programmed for the engine its running so it knows which injector to ground, to open it, according to the firing order

 

[Rounder]

Thank you Ron! You guys have it all!

I am working on a 1999 4.0 OHV and it has 1 ground wire per cylinder.

 

[RonD]

1999 4.0l is the same as 1997 pin/wire colors above

 

[Rounder]

Thank you Ron, looks like I have them correct.