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My dad has a 98 Outback (early)with 2.5 DOHC 5 speed. Engine check light has been coming on. I checked the code and it was a 32 for the oxy sensor.I cleared the code and it came straight back. Does this car have 1 or 2 of these? I can only see 1 without getting underneath it.Is this a serviceable item? Can I clean it? if it has 2,how can I tell which 1 is crook? Are they expensive? Thanks in advance for any help.

one on the inlet one on the out let the one on the inlet can be sprayed clean and replace the exhaust one

alang wrote:one on the inlet one on the out let the one on the inlet can be sprayed clean and replace the exhaust one

On what inlet?

Yeah grab a new sensor from ebay. Any 3 wire sensor will do, you just have to swap the connector so it plugs into your loom

http://www.ebay.com.au/itm/SUBARU-IMPRE ... SOR-3-WIRE

Thanks Gannon, so is there only the 1 in the exhaust? Never heard of 1 on the inlet either. Does the turbo one this links too on fleabay fit non turbos as well?

Sorry Gannon, just read the rest of the ad, Doh! Will try to get the numbers off it and search fleabay again or get in touch with this mob, cheers!

They only have 1 Oxygen sensor prior to the Cat. There is a exhaust temp pyro after the Cat which is a single wire sensor but like Gannon has mentioned the Oxygen sensor will have 3 wires.

You can not clean them. You can check them by grabbing a copy of the FSM and using a multimeter.

forgot to add cat model have two. you can get a spray from supershit for the intake air flow to manifold one to prolong its life made by CRC around the $24.00 mark. the air intake ones don't like water and stuff up faster when wet

I think you are talking about the air flow meter, which is nothing like an oxygen sensor.

alang wrote:forgot to add cat model have two. you can get a spray from supershit for the intake air flow to manifold one to prolong its life made by CRC around the $24.00 mark. the air intake ones don't like water and stuff up faster when wet

So we replaced the front one,and it seems to be more responsive.There is only one on this car. Still cant clear the code and tried both methods found on this forum and in the book,code 32 (oxy sensor circuit) keeps coming straight back. Tested the new oxy sensor with a volt meter as per the Haynes book and it shows battery voltage or thereabouts at 1 pin and 100 millivolts at the other, but output doesn't seem to change as the car warms up, does this indicate a faulty new oxy sensor? Not sure if I am checking this correctly though.Just want the engine check light to stop coming on.

Be wary that any EFI car that logs a DTC does not always mean the sensor is faulty.

Could be a wiring fault.

What fuel are you using? Please don't say E10.

Did you keep a receipt for last fuel purchased?

Definitely not had E10 in it says my old man, anybody else think the new oxy sensor may be crook? May have to buckle and take the car somewhere soon.

E10 won't affect your oxygen sensor.
Get a digital multi meter and test the between the oxygen sensor wire at the ecu and earth. If the oxygen sensor is working the voltage should fluctuate between 0 and 1 volt. If its dead, you will have to replace it. Ecu is located in passenger footwell. Ill give more detailed info when i get home from work.

Sent from my new touchy phone thingy

Thanks Gannon, I suppose that doing this will check the actual circuit. Had not considered that. Any more info, like what colour the wire might be between the ECU and the oxy sensor connector? Or the pin location on the ECU? I do have a book, but dont trust it too much as the wiring colour codes so far havent matched what was on the old sensor or the new one.

Ummm.... cant find the ECU in the Pass footwell, not behind the kick panel, could it be under the drivers kick panel near the fuse box? Book doesn't say so.

The ecu is located under a metal plate where the floor angles up towards the firewall. You will have to remove 3 bolts to remove the metal plate to get access to the ecu

The white wire going to pin 38 is the one you are testing. Under acceleration, it should be up around 0.9v (rich), when backing off, it should drop to around 0.1v (lean) and while cruising, it should alternate back and forth, showing the ecu is in closed loop mode

Thanks Gannon, you are a bloody legend!

Ok, first thing is to say a huge thank you to all who advised with this issue, esp. Gannon, thanks.
Dad went shopping and bought his new oxy sensor from A**obarn, and that was the problem. It was the cheapest 1 that anybody had in stock, brand unsure. Took it in to a garage to sort it out in frustration and found that the ECU had been damaged and needed remedial work inside, told it was the oxy sensor circuit that was damaged. They fixed that and fitted a secondhand sensor and sorted out the wiring because none of the colour codes matched up and they reckon it was the sensors fault. All up about $600 later, not too bad really,Dad is now going to take the faulty new sensor back and see if they will cough up for some of the cost of the repairs, which I think they are liable for but dont like his chances, or at least get his $110 back for the price of the sensor. Car running heaps better and Check Engine Light staying off so far.

I'm not quite sure what your saying. So the cheap o2 sensor has damaged the circuit? I'm in a similar position to you, i'm going to a wrecker on friday to triple check my sensor is doing what it should. Did the mechanic need to re-wire from the sensor plug to the ecu?

outtheback97, we were told that the cheap oxy sensor (fuelmiser brand) had damaged the ECU because the wiring was incorrect on it. I was not involved in talking to the guy who eventually sorted it out, so I am relaying what my old man tells me.He is 83 and self confess's that he suffers from "Cant Remember A F**king Thing" or CRAFT. I am therefore not 100% sure what was wrong that caused the issue with the ECU, but I am happy it is sorted. I thought of trying several things, but decided to leave well enough alone. He is happy now after all.
I got the impression that he did fix some wiring between the sensor plug and the ECU, but not sure what.
I guess if we had of got a Bosch or Denco 1 it may well have fixed it the first time and we would have looked bloody clever!
Buyer Beware I say, avoid the cheapies.

CRAFT, classic. I suffer a little from that as well, and i'm in my twenties. It just so happens that I bought the same brand sensor as you guys. We'll see, thanks for the reply.