Oxygen Sensor

[gary_cs]

I have a 2000 996 Carrera Cab my service light keeps coming on. My OBD code I'm getting is P1126 (02S Sensing Range 1 CYL 4-6). I bought a new Oxygen Sensor is CYL 4-6 the passengers side? is there anything I need to do before I start replacing this sensor? Thank You for any help.

[Loren]

P1126 Oxygen Sensing Adaptation, Lower Load Range, Bank 1 – Above Limit, or Below Limit

This means that the fuel mixture is too rich and the DME software can not correct for it. This is not an O2 sensor problem.

 

Possible causes are:

– Incorrect signal from MAF sensor
– Fuel pressure too high
– Fuel injector fouled

[Ahsai]

Hi Loren,

 

Can this code (for DME7.2?) mean either too lean or too rich and you really need to look at the fuel trims to confirm? The code description says "Above Limit or Below Limit".

[Loren]

Yes, I took that from my Porsche 7.2 OBD II manual.

Fuel trims should looked at. Since this is a bank 1 issue compare the readings to bank 2.

[gary_cs]

8 hours ago, Loren said:

P1126 Oxygen Sensing Adaptation, Lower Load Range, Bank 1 – Above Limit, or Below Limit

This means that the fuel mixture is too rich and the DME software can not correct for it. This is not an O2 sensor problem.

 

Possible causes are:

– Incorrect signal from MAF sensor
– Fuel pressure too high
– Fuel injector fouled

Thank you Loren. Could I clean the MAF sensor with the (Mass Air Flow Sensor Cleaner)?

[Loren]

Always worth a try.

Give it time to work though.

[judgejon]

For sure try to clean the MAF first.  Even replace it if there is any doubt.

If it turns out you do need an O2 sensor, I would replace all 4 of them at the same time.  I think there are 4 on the 2000?

Good luck.

[gary_cs]

On ‎7‎/‎18‎/‎2016 at 6:12 AM, Loren said:

P1126 

On ‎7‎/‎18‎/‎2016 at 2:42 PM, Loren said:

Always worth a try.

Give it time to work though.

Adaptation, Lower Load Range, Bank 1 – Above Limit, or Below Limit

This means that the fuel mixture is too rich and the DME software can not correct for it. This is not an O2 sensor problem.

 

Possible causes are:

– Incorrect signal from MAF sensor
– Fuel pressure too high
– Fuel injector fouled

Hi Loren, I was able to take back the Oxygen Sensor and ordered the MAF sensor. When it came in it looked like the one I had, but it wasn't. I took it back and also brought the one from my car. When they looked it up the only one they were able to match it with was for a 2000 996 Carrera all wheel drive. As far as I know this is a 2 wheel drive?

[Loren]

MY2000 Porsche made some changes as all Carreras became e-gas.

If your car had the non-egas version sensor that would be odd and likely would not work well.

If it was that way from the factory then you would need a DME software update for the new sensor to work.

 

I guess you can try and if it solves your problem - then great.