Hi

I had a CEL light on the other day when I did a scan it came up with P0136 Oxygen Sensor Circuit Malfunction (Bank 1 Sensor 2) is this right as the car is mapped and de catted so dont understand why this is coming up as if the car has been mapped this error message should not show up as I belive when its been mapped it tells the ECU to forget this sensor

help would be appreciated

Stu

 

The CEL mapped out would be P0420 for the missing cat.

I'll have a look at the OBD II codes

Shaun

 

Thanks again Shaun

She is going in for some work tomorrow as apparently the various vac pipes under the intercooler aren't on correctly could this be a possible cause?
Stu

 

P0136 is a circuit malfunction...either the sensor is on the way out or there is a loose wire somewhere. Even though the de-cat CEL has been mapped out, the ECU still expects to have a working rear 02 sensor.

HTH

Shaun

 

double post

 

thanks Shaun

I will get another sensor and see if that fixes it hopefully it will

 

I'd check the wires and connections for the 02 sensor first

Shaun

 

Spoke to Bob last night who did the maps for my car he said that the o2 should not be throwing up a fault as the rear o2 sensor hsa the values really high so should not throw up any error codes, so might unplug and see if that works.

Also he said the car has two maps on and the way I can switch between them is to have ign on foot to the floor press the heated rear window button then release my foot then turn the rear window off and aprently he said that switches between the two maps one is at 1.1 bar and one at 1.3 bar

i never knew that

 

i have this code pop up all the time and got it diagnosed at subaru and they said i needed a new front 02 sensor ?????????? have a p0171 that pops up less frequent

 

I guess you mean Bob "Guru" Rawle he squeezed a shade over 400 BHP from my methanol injected bugeye.......legend !!

Bob would have told the ECU to ignore the rear 02 sensor saying that the cat is running below efficiency (the P0420 CEL) but the rear 02 sensor is still monitored by the ECU and if it thinks it's broken or there is a bad circuit connection then it will throw a CEL

It's not that simple !

http://en.wikipedia.org/wiki/Catalytic_converter


If the Front 02 sensor is playing up then the ECU could get confused but I doubt it.

The Bugeye ECU does not have enough room on the EPROM for two completely individual maps but can cope with a switch to a low boost setting independant of the fuel / ignition map (foot to the floor and rear demister LOL)

Unplugging the rear 02 sensor will just let the ECU think it's completely broken..

Any good subaru specialists near you ?

Cheers

Shaun

 

oops....have I answered your PM ?

Shaun

 

Yeah I use a garage called SRi in Adlington Simon who used to be my old boss knows his stuff about Soobys as he built a monster of a SUB

When I spoke to Bob he said that I could just unplug the Rear O2 sensor as the values where really high and it should not be picking anything up at all.

She is going in on Saturday to have all the vac pipes under the intercooler changed and refreshed also making sure its running A1 so he will have a look then