Idle went haywire last night, possibly the o2? 84 4kq

[Tony Hoffman]

You unplug the single black wire that comes off the O2. I believe it's
the one that plugs into the green wire that then runs to the ECU. The
two white wires are for the heater in the O2 sensor.

On this note, I also install four wire O2 sensors on my cars. The
additional wire is a dedicated ground for the O2 baseline. The stock
setup relies on the Exhaust system for it's ground. After years of
rusting, I don't trust it. I haven't actually noticed a huge
difference in the 4000, but it can't hurt, In the V8, the difference
was night and day. Then again, the 4000 doesn't exactly have the
horsepower of the V8, so I don't know that it would be as obvious :(

The other reason I like the 4-wire is it's cheaper. I get them for about $45.

Tony


On Sun, Dec 5, 2010 at 11:11 PM, Vincent Gelinas <vrgelinas at gmail.com> wrote:
> In the same vain of testing the o2 sensor on my 89 90q, I have the plug to
> the harness and I have a green wire next to it. Which is the one I should
> unplug to return the edu to a baseline?
>
> Thanks
>
> Vincent.