At 12:44 AM 1/14/2003, Claudio Cella wrote:
>Hello to all, while on the topic of O2 sensors:  if i understand correctly
>if the sensor shows no volts (bad sensor or no sensor)ecu defaults to open
>loop which means running rich.  Is there a way to run without the O2 sensor
>and trick the ECU into running lean?

No, if the sensor is open the ECU will bias it to very close to 500
millivolts.  A sensor reading 0 volts (from grounding or whatever reason)
will cause the ECU to richen the mixture until the ECU runs out of
adjustment room, and your mileage will go down to about 10 mpg (whatever
that is in l/100 km -- anyway, it will drop by close to half).

To run without the sensor, just unplug it.  The ECU will go open-loop and
if AFM etc. are correct it will run fine, but emissions will go way up.  If
AFM is off it will run too rich or too lean.

d

--
David Beierl - Providence RI USA -- http://pws.prserv.net/synergy/Vanagon/
'84 Westy "Dutiful Passage"
'85 GL "Poor Relation"