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

[Vincent Gelinas]

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.

On Dec 6, 2010 12:07 AM, "Tony Hoffman" <auditony at gmail.com> wrote:
> Jonny,
>
> Glad to hear you are making progress. So, the Idle and full throttle
> switches are opperating properly now?
>
> One quick way to test the O2 is to unplug it and see how the car runs.
> You only have to unplug the single black wire, that's the one with the
> signal to the ECU. The car will go to a base default setting, and
> should run better. If that's the case, you have found for sure the O2
> is bad.
>
> The other way to check it is with a volt meter. Should fluctuate
> around .2 to .8 or so volts. Yours is probably stuck closer to 0
> volts, telling the car it's lean and causing it to dump extra fuel in
> to compensate.
>
> Tony
>
> On Sun, Dec 5, 2010 at 10:28 PM, Johnny B <pre95 at live.com> wrote:
>>
>> Well I've made some headway! I found that my idle switch button was
actually funked up making the 'click' a very hard press (grease & grime
build up). After some contact claner & q-tips it clicks as it should, and
now responds as it should. With the idle switch working I adjusted the
static setting back to where it was marked when done with properly tuned
with the voltmeter (I've tracked all static adjustments so once sorted I
could return it to where it should be) which gave me a silky smooth idle..
that is until its heated up. Once ran on the highway for a bit it's back to
gas fumes @ idle and a varying idle (drops kinda low then jumps back up,
low, then back up, then it will kinda stabilize but still very rich) so now
it's back to a borked o2 sensor but this time around Im very excited knowing
once replaced I will have a smooth idle once again with the switch now
repaired.
>>
>> 2 birds with one stone, I found while having the intake boot off I could
see my exhaust leak culprit (loose flange nuts) which got a good buttoning
up. Still a bit of a leak but much much less (Im assuming some of the bottom
nuts may be loose as well, I'll be checking in to that during the o2
replacement.)
>>
>> Thanks for the kick in the motivation here guys, it's becomes tiresome
chasing that next broken part sometimes.....
>>
>> Johnny
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