Okay, so i have three wires that are not in contact with anything. they are as follows, Green/purple (coming from a sensor on the intake manifold), black/yellow, and a tan/yellow. i have no idea what they are for. start up is normal most times but i am stumped on what these wires are to and for. any help would be appriciated! thanks!
Are you having problems with your vehicle? Are you getting error codes from the computer? If not, then there's no reason to worry about those wires.
The wires may have been intended for options or equipment that your truck's original configuration lacked. To save money, they built every main harness the same, with connectors for all the possible options. If your truck never had a cruise control, or an air-conditioner, or an automatic transmission, or similar, then there will be wires in the harness that don't connect to anything, where those optional parts would have been.
If your really concerned about them, go look up the wiring diagrams in the Tech Library for your model year, and figure out what they go to.