- O2 sensor vs. Air-Fuel sensor
- Posted by Rohit Chadha
Hello All,
I was wondering if the auto techies here can tell me the difference
between these two. Apparently, my Camry 1999 I-4 has a code of P135 when
Check Engine light came on. I referred to the Camry Haynes manual and it
reports heated O2 sensor but am wondering if both of these are the same or
are the functionalities different with each of these.
Thanks.
- Posted by Jason James
"Rohit Chadha" <rohitc@speakeasy.net> wrote in message
news:TqOdnYnAKZ5UeQLcRVn-2g@speakeasy.net...
There are a number of mixture sensors which work by totally different means.
See this page for an excellent comparison of the O2 sensor vs a linear
air-fuel ratio sensor
http://www.insightcentral.net/encyclopedia/enlaf.html
Jason
- Posted by MB
It's the same thing. T uses a heated version of the o2 sensor, a 4 wire
variety. They call it an AF sensor.
Expensive from T, bosch and others have em for about 70. Sometimes you
have to put the connector on it yourself.
Rohit Chadha wrote:
- Posted by Philip
Sorry MB ... you are in error. While the two are similar in appearance,
they are functionally different and not interchangeable. Jason provided a
good link for you to read:
http://www.insightcentral.net/encyclopedia/enlaf.html
--
- Philip
Nov 20, 11:03pm
Bridgeport, CA - Cloudy 24° F H35°/L10°
"MB" <mkb@sonic.net> wrote in message news:41A038EA.A3B034CC@sonic.net...
- Posted by MB
Phillip,
Thank you for correcting me.
Do you KNOW of any other device that will do the job?
best respects,
mb
--------------------------------------------
Philip wrote:
- Posted by Philip
Odd question ... considering the title of this thread.
The Air/Fuel sensor voltage signal is relatively proportional to the exhaust
oxygen content. As the air/fuel ratio spans 12:1 to 19:1, the ECM monitored
voltage spans 2.4 to 3.9 volts respectively. This is quite different from
an O2 sensor whose produced voltage ranges from 1.0 volts at 14.3:1 down to
0.2 volts at 15:1 air/fuel ratio. The O2 can't tell the ECM how MUCH beyond
a vary narrow range the air/fuel ratio has gone. This is why the two
sensors are not interchangeable. To add to the confusion, there are those
models that do use an O2 sensor before and after the catalyst but these
systems use the 02 after the catalyst for a different purpose.
- Philip
"MB" <mkb@sonic.net> wrote in message news:41A16565.66BCDACE@sonic.net...
