Oxygen Sensor Operating Temperature
Alan Kramer
ackramer at hotmail.com
Wed Aug 30 16:07:07 EDT 2000
Is there a minimum recommended operating temperature for an oxygen sensor?
If so, will the heating element in a 3 or 4 wire sensor be sufficient to
maintain that temperature, or must the exhaust gas be at or above that
temperature?
The reason I ask is that the table I have that compares voltage to mixture
ratio explicitly states the relationship was derived for a sensor
temperature of 1200F. If the temperature of the combustion gas is lower, is
the curve offset or skewed, or is it just that the response of the
electrochemical cell is slower?
Does anyone know what the exhaust temperature just prior to the cat on a 4kq
would be? My feeling is that it is signifiantly lower than 1200 F. I'm
running a 4kq header & downpipe on the '83 CGT and have my two oxygen
sensors (1 for computer & 1 for mixture guage) located 6" after the
termination of the downpipe next to the tranny. When driving at WOT, the
oxygen sensor voltage does not go above 0.65V. I have verified operation of
the WOT switch, fuel & control presures, flow rates, etc... and all is in
spec. Although it is an '83 CGT, it was "upgraded" to CIS-E. Mixture is
set correctly. Even adjusting to full rich settings (verified by idle
stumble, fuel smell out of exhaust (no cat)) and sending the computer into
open loop still does not result in readings above 0.65V while driving.
Swapping oxygen sensor leads to the guage does not change the results. My
thought is that it has to do with the temperature of the sensor...
Thoughts anyone?
Alan
'83 CGT http://www.geocities.com/audikramer/index.html
'86 CGT
'86 4kcsq
Thanks,
Alan
_________________________________________________________________________
Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com.
Share information about yourself, create your own public profile at
http://profiles.msn.com.
More information about the quattro
mailing list