The cable is under the hood and it has a an adjuster wheel..that cable has to have 1/4" slack at idle position...and it has to move freely.

On the pin 8 code, you want to try a few easy test.
First one it to take the vac hose off the fuel pressure regulator and look for any evidence of fuel/vapors..that would cause the rich mix and throw a code. Again , " fuel pressue regulator" in achives..tells all about it in detail
Second is to look for vac leaks everywhere....