Oxygen Sensor

[Huw Powell]

http://audi.humanspeakers.com/isv.htm

On 5/26/2015 7:50 PM, David Vanden wrote:
> Please explain, "You should try cleaning the ISV (use carb cleaner,
> actuate it momentarily with a 9v battery each way a few times)."
>
> I soldered a set of the throttle body switches I got.  Unfortuneately,
> they read they had some resistance as opposed to being infinite when the
> switches were not activated.  I don't know what happened to them in the
> process of pairing and soldering them.  However, they were both at a
> perfect 0 when activated so I used them.  I don't think they would
> increase the idle?
>
> This is a 1987 Audi 4000 Quattro.
>
> On Tue, May 26, 2015 at 7:19 PM, Huw Powell <audi at humanspeakers.com
> <mailto:audi at humanspeakers.com>> wrote:
>
>     You should try cleaning the ISV (use carb cleaner, actuate it
>     momentarily with a 9v battery each way a few times).
>
>     At rest it's about 1/3 open, which lets the engine run if it is broken.
>
>     The computer runs it whenever the idle switch is closed to let the
>     right amount of air around the throttle body.
>
>     Test that switch as well, it's the one under the TB, a pair of the
>     pins at the connector on top of the TB should read 0 ohms when the
>     throttle is closed and open to infinite when it is just barely cracked)
>
>     Also, disconnect every electrical connection under the hood one at a
>     time, clean, and reconnect using dielectric grease.
>
>     I hope this helps.
>
>     - Huw
>
>     PS, what year and model is it?
>
>     On 5/26/2015 4:00 PM, David Vanden wrote:
>
>         I will put in an oxygen sensor.  Thanks for the advice.  On a
>         separate
>         note I just replaced the fuel pump and she is idling too high.
>         I tried
>         adjusting the mixture but that didn't fix it.  Any ideas?
>         Decreasing
>         the air on the throttle by setting the screw all the way to the
>         right
>         decreased it but not enough.  Any suggestions?
>
>         David
>
>         On Tue, May 26, 2015 at 2:54 PM, Huw Powell
>         <audi at humanspeakers.com <mailto:audi at humanspeakers.com>
>         <mailto:audi at humanspeakers.com <mailto:audi at humanspeakers.com>>>
>         wrote:
>
>              Short term, for testing or diagnosing, it will run.
>
>              Startup will be normal, but when the engine gets to operating
>              temperature, the computer won't be able to manage the
>         mixture properly.
>
>              Run without it for any length of time - like leaving home -
>         can do
>              very bad things to the catalytic converter.  Fuel economy
>         will also
>              suffer.
>
>              So first test if the OXS is working.  Then if it isn't,
>         replace it.
>              Yes, I know, if this is a 4kq, it is *very* hard to get to,
>         and it
>              will be rust-welded in place.
>
>              This might help:
>
>         http://audi.humanspeakers.com/timing2.htm
>
>              - Huw
>
>              On 5/26/2015 11:17 AM, dvanden46 at gmail.com
>         <mailto:dvanden46 at gmail.com>
>              <mailto:dvanden46 at gmail.com <mailto:dvanden46 at gmail.com>>
>         wrote:
>
>                  Has anyone noticed if it is detrimental to the car or
>         if the car
>                  runs worse with the oxygen sensor disconnected?  This
>         is for the
>                  CIS E system.
>
>
>
>
>
>
>                  Sent from Windows Mail
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