I received new front O2 sensors and the wires were not covered well. It was pretty easy fix with heat shrink.
1. Take picture of back of plug for wire color/pin location.
2. Gently pry off yellow cap, you can see little spaces on the side to slide in a small screw driver.
3. With a tiny jeweler screw driver, release the tab and pull out the 4 pins (go youtube and see the videos if you don't know how to do it).
4. Cut to length heat shrink and shrink tubing. Reinstall old nylon chaff guard (or get new full length nylon chaff guard).
5. Repin plug and snap yellow cap back on.