This product is what I used for a DIY insulation solution. I pulled back a lot of the hard-plastic wire covers (not the rubber insulation that is cracked, but the black plastic tubes the wires route through) to make sure I could see where the insulation cracking stopped and then used the product to re-insulate all wires. You have to be patient and go through the whole car, and there are no guarantees this will fix the problem, but its worth trying. In my case I had a crank sensor code and could see that the bare wires on its connector were touching (i.e. shorted), so it was easy to fix.
