OBD1/ OBD2 02 sensor locations.
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BOOST GOD
Joined: Apr 2003
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From: NL CT
OBD1/ OBD2 02 sensor locations.
I needed to replace my a-pipe (lower-portion of my header, the collector portion). And the one I got doesn't have an 02 bung, but it is reportedly from an 1998(obd2) car.
For a better visual, it is missing one, before the cat.
Is this an obd2 a-pipe, or have I been misled.
I was under the impression that all obd2 setups had two 02 sensors, one before the cat, and one after.
Luckily, my ecu is obd1
-PHiZ
For a better visual, it is missing one, before the cat.
Is this an obd2 a-pipe, or have I been misled.
I was under the impression that all obd2 setups had two 02 sensors, one before the cat, and one after.
Luckily, my ecu is obd1
-PHiZ
Flaccid Member
Joined: Jul 2002
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From: Seattle
OBD II has 2 O2 sensors as you describe. you've been bamboozled with that replacement A-pipe.
if you're OBD I converted, you still need the forward sensor... it's the only one that will give you accurate readings for the fuel mixture.
if you're OBD I converted, you still need the forward sensor... it's the only one that will give you accurate readings for the fuel mixture.
wooooo woooooooooo
Joined: Mar 2002
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From: Twin Cities
If it's a D series, the secondary O2 goes on the cat itself, not on the manifold. So you'd have one where they all go on obd1 cars (on the upper half of the manifold), and another on the cat.
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BOOST GOD
Joined: Apr 2003
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From: NL CT
Originally posted by Bakeoff
If it's a D series, the secondary O2 goes on the cat itself, not on the manifold. So you'd have one where they all go on obd1 cars (on the upper half of the manifold), and another on the cat.
If it's a D series, the secondary O2 goes on the cat itself, not on the manifold. So you'd have one where they all go on obd1 cars (on the upper half of the manifold), and another on the cat.
If the obd1 02 sensor location is higher up on the manifold, I believe that makes it a 1-wire 02 sensor, i.e. an 02 sensor without a heating element. Hence the placment near the manifold to heat it up.
So I guess I need to: tap an 02 bung in the a-pipe/collector, and then make sure I am using an ecu that can control the heated sensor. I am using a p28 currently.
-PHiZ
のんびり～(´ε｀)
Joined: Sep 2000
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From: San Jo, Cali
I have a 97 Civic. My stock manifold had the primary heated O2 on the #3 runner. Placement of the O2 doesn't necessarilly correlate to it being heated or non-heated. OBD-I cars for the most part use 4-wire heated O2's. The only cars that I have seen non-heated O2's on were non-OBD, or OBD-0. Your P28 will have no problems running a 4-wire heated O2, unless it's been modified to run a single-wire O2.
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BOOST GOD
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From: NL CT
Originally posted by inspyral
I have a 97 Civic. My stock manifold had the primary heated O2 on the #3 runner. Placement of the O2 doesn't necessarilly correlate to it being heated or non-heated. OBD-I cars for the most part use 4-wire heated O2's. The only cars that I have seen non-heated O2's on were non-OBD, or OBD-0. Your P28 will have no problems running a 4-wire heated O2, unless it's been modified to run a single-wire O2.
I have a 97 Civic. My stock manifold had the primary heated O2 on the #3 runner. Placement of the O2 doesn't necessarilly correlate to it being heated or non-heated. OBD-I cars for the most part use 4-wire heated O2's. The only cars that I have seen non-heated O2's on were non-OBD, or OBD-0. Your P28 will have no problems running a 4-wire heated O2, unless it's been modified to run a single-wire O2.
So inspyral, if your "forward" 02 sensor location is on the primaries, I'm guessing you don't have any on the collector. And I do have an obd2 a-pipe.
so let's see what we got:
your car: 97
donor car: 98
my car: 99
I wonder if the 02 sensor location correlate to OBD2a vs. OBD2b ???
nope
OBDII A (96-97) and OBDII B (98-00) connectors.
WTH
Also, I have it on good authority that the p05 ecu uses 1 wire 02
So, what would be easier, cutting the good flange off the non-bung pipe, and welding it on to my existing a-pipe w/bung.
or
Drill-pressing a hole in the non-bung a-pipe, and welding a bung? Anyone got the specifications of the bung on-hand?
-PHiZ
のんびり～(´ε｀)
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From: San Jo, Cali
96-98 is OBD-IIa, 99-00 is OBD-IIb
If you need to have an O2 bung added, it should only take about 5 minutes at a muffler shop. They'll have the bung there, or you can order one from Summit for about $5.
If you need to have an O2 bung added, it should only take about 5 minutes at a muffler shop. They'll have the bung there, or you can order one from Summit for about $5.
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BOOST GOD
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From: NL CT
Originally posted by inspyral
96-98 is OBD-IIa, 99-00 is OBD-IIb
96-98 is OBD-IIa, 99-00 is OBD-IIb
I dunno, I respect both of your opinions so much, I can't decide...
I just asked the guy that sources my ECUs and harnesses, and he pointed me to this chart he did up, reposted here with his permission.
apparently you have to take into account the year of car, but also model...
http://www.crimethink.org/images/obd2_years.html
-PHiZ