1998 EJ20 oxygen sensor code, But new sensor

[Nofailure2Fail]

Hello Folks

 

I have a 1998 legacy with ej20, a couple of months ago the engine light started coming on when the car was pulling hard/heavy, but went away again on flatter, easier roads. I read the codes and it said it was the oxygen sensor, so i bought a new genuine subaru one and put it back in. Just after 2 days the lamp comes back on again, same as before, only on when cars working hard. Code again says oxygen sensor. I measured the wiring and sensor and everything seems it be like it should so it seems something else is triggering this code.

 

Anyone else experienced similar and have any thoughts? any other sensors thats failureprone on these older ej20s?

 

Car has very low milage and engine is pretty mint except for this engine light problem.

 

Thanks in advance for any help

[08SpecB_DE]

What's the code description? The car could be running lean or rich under heavy acceleration that will throw a false o2 code. The cat could also be an issue.

[Nofailure2Fail]

Hi

 

The code only says; 32 Oxygen sensor or circuit

 

I suspect the car is running rich since i can smell gas, However the car runs a lot better now with the new sensor then it did with the old, yet the light still comes on.

[doublechaz]

What market are you in? A 2nd gen US car should have OBDII standard codes of the format P####. It should also have two oxygen sensors. Finally, the OBDII would give a code that specifies which sensor is off. The code you give looks like an OBDI code like in a 1st gen car.

[Nofailure2Fail]

Im in Europe. From what i read online my car should have obdII, but i have been looking thru the entire underside of the dash without finding a socket, all i find is the old style green and black wires to hook together, so either it doesnt have it, or i cant find it.

[Keyan]

if the code says sensor or circuit, and you replace the sensor and it still happens, you're probably looking at a circuit issue.....best you test the wires and maybe check for mouse damage.

[doublechaz]

From what I see it should be above and right of the hood release behind a little door. But that is internet info, so YMMV.

[solosouthpaw]

I'm looking for what the voltage range is supposed to be on the o2 sensors, backstory below:

 

98 2.2l. Was told it needed new cat, both o2 to fix CEL.

 

So, new BOSAL cats, front and rear, plus center pipe, all new flanges, and a set of BOSCH o2 sensors. CEL stayed off for ~100 miles, then came on at idle this morning. I have a dongle and Torque installed on android and reset the CEL and started logging. Drove about 10 miles (10-60 mph) and CEL came on again.

 

Voltage was varying between 0.0v and 0.8v on both.

 

CEL CODE : P0453

 

My thoughts are:

 

1. Per the other post here, check my wiring on that circuit for damage/mice

2. Bad ground wire on the vehicle/battery

3. Bad o2 sensor

4. Some other emission related item

[doublechaz]

That is a normal O2 voltage range. If you are going a steady speed on level ground I would expect them to wobble around the .5v area for the front sensor.

 

P0453 is an EVAP code. I would look around for wires and vacuum/breather lines that might have been damaged/disconnected during the other work.