ambient AFR reading

[tomita]

I've got ~19 AFR reading w.cold engine off (new sensor in downpipe). Is this value ok, or may i adjust the Pump zero pw value a bit, to get around 20.5?

[rob@vems.co.uk]

You need to take the sensor out of the downpipe to test it.  Don't mess around with the PW Zero value as it will at best make the sensor read incorrectly, and at worst damage the sensor.

[tomita]

Thanks for the advice, will test it that way.

[j bjork]

I have the same problem, it shows around 19,5 whith the sensor out of the exhaust.
I have a bunch of problems sinse i upgraded the software.
First i put in the newest "2009 something" software, then it got locked.
After erazing and installing the "2008 something" software, it works, but not like iI want it to..

[rob@vems.co.uk]

When you say "not like you want it to" what is it not doing that you want?

If the sensor has been in the exhaust it will read rich because its covered in soot, leaving it out hot for a while will see the value rise, also taking a lighter and putting the sensor in the flame will help burn off any of the soot, but personally I'd not mess around with it.