I have 4 wires with no identifiable home. 2 red with white stripe, 1 blue with white stripe and 1 black with some stripe, could be yellow. I could not locate them in the diagrams I have. It does have a EGR and a CAT indicator so maybe they go there. They have the small connector where as the rest have the wider connector. Any ideas? Thanks

Here. Is good place to. Start checking and tracing.

Click to view attachment

Mine has a number of homeless wire also but everything works.

That is the one of the diagrams I used. I guess I'll tape them off for now. Thanks..