Today I unplugged the OxS sensor black wire and it appears that the car idles just as bad as before. First of all I can only find 3 wires on my OXS sensor, two white and a black one with a boot on it. I'll try and replace it even though it's 3 years old with about 10000 miles on it, 99% city driving unfortunately. Any tips on the procedure or it's plain easy ? thanks