Well once again I need some K5 wisdom. My wiring harness has been in a box for about a year. I've nearly got everything hooked up, modified, upgraded and working. However, I'm scratching my head about the small harness that goes into the firewall above and right of the fuseblock harness. Two wires go to a vaccuum controlled switch mounted on the intake manifold. It is connected to a relay under the dash. What does this system do? Also this harness has a heavy (10guage) red wire running from under the dash. My guess is a power wire running from the fuse block to something, but what? Haynes and Chilton have hidden the answers from me, please help!!