o2 sensor bank 1 sensor 1

[lsmask]

Hi not sure if im in the right place here but here goes
I have a 2003 bmw 318i and the emmision light has come on giving me codes p0030 which is H02s bank 1 sensor 1 heater circuit and po130 02 sensor circuit malfunction bank 1 sensor 1 any ideas really appreciated I can only see two sensors in midddle of car underneath none up near engine

Edited by lsmask on Monday 7th January 21:18

[Enginostics]

Hi, bank 1 sensor 1 is the pre-cat sensor, the one closest to the engine, like you say. I would scope the output from the lambda sensor. Rev the car to 2000rpm using a pogo stick on the accelerator pedal and monitor the output from the lambda on the scope. If it is a four wire sensor, two white wires for the heater element, gray wire for signal output ground and black wire for signal output, then it should switch at 1Hz (1 times/sec) and switch between 0.2v & 0.8v. I would recommend the replacement of lambda sensors every 25000 miles as they are a critical part of the injector system.