My room mate just made the switch to Volvo, and I found him a good deal on an 85 240, for $300. It has a small fuel problem, and were hoping that replacing the fuel pump is going to fix it, or else we will keep digging from there I guess, haha. Anyway, the odometer reads 112k, and the car is pretty clean. I noticed that the notorious engine wiring harness has no damage or melted wires on it yet. My 86 with 220k miles on it wires were completely destroyed. Is there any preventive measures, or methods of reinforcement to help keep these wires from getting too hot and melting in the future?

 

The issue isn't really getting hot and melting. The issue is the insulation biodegrades into dust. Then bare wires touch, melting and all sorts of neat things happen. You can either band-aid it together as ish happens or swap in a later replacement harness with decent insulation. davebarton.com has all the o.e. part numbers as well as replacement part numbers for the harnesses. With the numbers in hand, you can scour j/ys for a new one.

 

here's a good link for making your own harness:
Wiring Harness Guide | K-Jet.org

 

Its entirely plausible someone already changed out the harness? The gray connector is a good place to check, but also check the plastic elbows on the injectors, rate they cracked, get a flashlight and look down in between the intake and check the CTS wire how does it look, does the insulation peel away? If so proceed with caution because your harness may not be good.