i have a 96 gsr, and my stock header doesn't have an o2 sensor. i bought one from a guy out of state and his had an o2 sensor. is his a obd1?

 

Correct me if im wrong anybody, obd1 gsr has two sensors, one on the header and one on the cat, obd2 gsr i think have both sensor on the cat. Something like that i dont quiet remember. If not then probably the stock header you bought is not from a gsr...

 

No, OBD-1 GSR only has one sensor. But it's in the inlet of the cat. So the header doesn't have a fitting.

The 2nd sensor for OBD-2 cars is AFTER the cat...

 

No.

OBD-I and OBD-II cars both have heated o2 sensors on the collector end of the exhaust manifold. OBD-I cars do not have an o2 sensor on the catalytic converter. OBD-II cars DO.

So,

OBD-I = 1 sensor on the exhaust manifold.
OBD-II = 2 sensors, one on the manifold and one on the catalytic converter.

OBD-I = anything before 1996 ( 1993/1994/1995)
OBD-II = 1996 and anything AFTER ( 1996,1997,1998..etc..)

 

OBD-I GSR doesn't have the same exhaust as an LS. It has a shorter A-pipe, & the catalytic converter has a longer inlet section. The O2 sensor is in the cat housing, but it's upstream of the monolith.

The A-pipe for the B18B is longer, so the sensor is in the A-pipe. Either way, the sensor is pretty much located in the same place w.r.t. the firewall/floorpan.

They changed that configuration a couple years after OBD-II, so the redesigned A-pipe doesn't exactly correspond with OBD versions.

 

so the one with the o2 sensor on the header could be from an LS?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by siblue_gzer &raquo;</TD></TR><TR><TD CLASS="quote">so the one with the o2 sensor on the header could be from an LS?</TD></TR></TABLE>Or a newer GSR. I don't remember what year the GSR switched over to having the O2 sensor in the A-pipe.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by loud_whispers &raquo;</TD></TR><TR><TD CLASS="quote">No.

OBD-I and OBD-II cars both have heated o2 sensors on the collector end of the exhaust manifold. OBD-I cars do not have an o2 sensor on the catalytic converter. OBD-II cars DO.

So,

OBD-I = 1 sensor on the exhaust manifold.
OBD-II = 2 sensors, one on the manifold and one on the catalytic converter.

OBD-I = anything before 1996 ( 1993/1994/1995)
OBD-II = 1996 and anything AFTER ( 1996,1997,1998..etc..)
</TD></TR></TABLE>

 

This is incorrect.


OBD1 GSR - 1 02 SENSOR ON THE CAT
OBD2 GSR (96-99) - 2 02 SENSORS ON THE CAT
OBD2 GSR (00-01) = 1 02 SENSOR ON THE HEADER, 1 02 SENSOR ON THE CAT