O2 Sensors: Front vs Rear differences
Thread Starter
Le Mans Master
Joined: Jan 2002
Posts: 9,036
Likes: 13
From: Edmonton AB
O2 Sensors: Front vs Rear differences
Can anyone explain what the functional differences are
between fr/rr 'Universal Fit' O2 sensors?
Its been suggested that the connectors are different.
I can understand that this might be the case for
'OEM fit' sensors, but Universal ones have a generic
connector.
Is there something about the thread or physical size?
What about functionality - is there some reason the
rear ones might have a different scale or output signal?
Thanks.
.
between fr/rr 'Universal Fit' O2 sensors?
Its been suggested that the connectors are different.
I can understand that this might be the case for
'OEM fit' sensors, but Universal ones have a generic
connector.
Is there something about the thread or physical size?
What about functionality - is there some reason the
rear ones might have a different scale or output signal?
Thanks.
.
Team Owner
Joined: Sep 2001
Posts: 62,160
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
On later years, there are sensors that come rear of the cats. These are not totally functional until 96, as they are required for OBDII operation to monitor proper converter function.
I see no reason they should be listed for an 89 though.
I see no reason they should be listed for an 89 though.
Thread Starter
Le Mans Master
Joined: Jan 2002
Posts: 9,036
Likes: 13
From: Edmonton AB
Originally Posted by vader86
I see no reason they should be listed for an 89 though.
listings in search of a heated O2 for use in the collector of headers.
I was given a 24700 after asking for an O2 sensor to fit a '95.
When you say the rears weren't fully functional, does that mean
the sensors are crippled, perhaps factory sims? Or is it the ECM
side of the equation that wasn't fully functional?
(BTW - I have a Delco AFS 74 number now from Doctor J)
.
Team Owner
Joined: Sep 2001
Posts: 62,160
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
They are on a 95, but the ECM is not reading their input for fuel/timing adjustment.
I would not use them on your car though.
I would not use them on your car though.
Large Impressive Member
Joined: Jul 2003
Posts: 65,811
Likes: 71
From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
FWIW, on my '95, all three sensors are the same part number. I don't even use a rear one anymore and it doesn't throw a code. I don't really understand what their purpose was (the rear one) before the complete implementation of OBD II in '96.
