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caplem
03-30-2010, 11:41 PM
where are the o2 sensors located?
I have a 2002 b4 (jap spec) and I cant locate the o2 sensors. how many does this car have and does anyone have part numbers
I think I found 2 the first one is in the left manifold (from the point of viewof sitting in the car looking through the windsheild) and the second is where the 2 manifolds meet under the car before contining to the muffler. the first one has 2 wires and the second has 4 wires the engine chk light is on and I got this code P0031 HO2S BANK 1 SEN 1 HEATER CICUIT LOW. where is Bank 1?

also if I am sitting inthe car looking through the windscreen where is the number 1 cyclinder located in relation to where I am sitting is it left side fwd cyclinder or right side fwd cyclinder?

jey
03-31-2010, 01:09 PM
The one on the manifold is probably an EGT sensor actually. Usually the 2nd O2 sensor is after the catalytic converter since it is just detecting the efficiency of the converter. The "Bank" is irrelevent for Subarus - there are obviously codes available in the OBD standards for other banks but you should never get a code for "bank 2" on a Subaru.

Robbks
03-31-2010, 06:42 PM
My 97 JDM LGT has it's only o2 sensor located in the LH exhaust header.

as a test, unplug it the one in the exhaust header (plug should be near the battery somewhere) and see if it causes a CEL with the same or different code.
Do the same with the rear o2 sensor and see what code that throws.
then you'll know which is which.

Plug everything back in, Clear codes, reset ECU. WIN!!

Driver
_____
3 4
1 2
Front

caplem
03-31-2010, 10:03 PM
ras pect will attempt this on the weekend and yes thought about the disconnecting scenario to see what codes came up will let u know as soon as i have tried it thanks all

caplem
11-23-2010, 12:03 PM
problem now fixed faulty fuel/air sensor in the fwd exhaust

Kiwi GT
11-23-2010, 01:27 PM
Sensor 1 is in the LH manifold, sensor 2 is where the downpipes meet by the back of the gearbox.
Bank 1 is the bank with cyl 1 in it, ie RH side, but because all exhaust gasses pass through the LH manifold on primary boost, the sensor in the LH manifold is bank 1 sensor 1.