Including unused wires on engine harness

Hello,

I’m currently planning my wiring harness for my project, and wanted to know what the best way to safely protect unused wires in my harness. Obviously I don’t just want to leave them dangling/un-sleeved.

I have plans of adding an ethanol content sensor and a 3-port boost solenoid, but not for a little while. Can I loop the wires back into the sleeving, or something else?

You can break them out to connectors that you can plug them into later when you add the other devices.

I often loop unused wires (that might be used for another application) into a 3" stub, that I cover with adhesive lined heat shrink. This leaves it sealed, an looking neat.

Would the dual-wall heat shrink not be a mess to remove when it comes time to use the conductors/wires?

I find it peals off rather easily. This is easy to test for yourself. You could cover the wires in kapton tape if you were worried about the adhesive sticking to the wire insulation.

I go with the same as Six_Shooter. Any unused outputs or inputs, I run to a short branch near the ECU and terminate with a DTM or Autosport connector. I usually add in a 5v/sensor 0v and or 12v/ground to make it easier if I'm adding in other sensors or actuators later. Makes it a lot easier to add in any extras at a later date and avoids hacking up your existing harness, especially if its a fully sealed motorsport spec harness.

In your case, because you already know what you're planning to put in later, I would suggest wiring what you need (12v, ground, digital input and aux output) to its own connector that you can later wire in a sub harness to your flex and boost solenoid. They can still be used for something else if the plan changes but makes life easier when those upgrades happen.

Planning ahead makes a world of difference with electrical.

Happy wiring!