Which other models/years have interchangeable parts with 1998 Volvo V70 AWD 2.4L Turbo? Particularly a wiring harness.

 

depends on the wiring harness. '98 S70 turbo should be mostly the same. If it isn't wiring that has anything to do with the AWD system, then FWD models should work as well.

 

It's the engine wiring harness. If you look at the pics in my profile you'll see that basically the whole right side needs replaced. Do you know if a wiring harness from a 2.3L would work with a 2.4L? Also do you know any other years that would work?

 

2.3L is likely the same thing. 97 or even 96 Volvo 850 turbo might be the same, or at least usable. 99 and up, even though the body is the same, won't work, as Volvo changed the entire engine management system in 1999.