Oxygen sensor question - 2002 BMW 330ci


#1

Got an SES (service engine soon) dash light about a week ago, and had autozone read the code(s). Using an actron they surfaced a P1087 which is the O-2 sensor, bank1/sensor 1.

Amazon has the Bosch OE ‘upstream’ O-2 for $52, so easy enough to grab 2 and just replace both.

My local Monro read the codes again, prior to putting the (2) O-2 sensors in for me and came up with ‘Lambda Sensor Frequency Controller’.

In my automotive ignorance (which abounds but I’m an avid ‘googler’ so very willing to learn) I see O-2 sensors referred to as Lambda Sensors and understand the concept of lambda.

So are the above 2 code reads the same, or is there a separate part called the Lambda Sensor Frequency controller? Any links to a good article on the topic(s)?

Any other insight, advice, tips, tricks, metaphysical enlightenment? In advance, mucho appreciation for helping a rookie along with his the newly acquired E46 convertible. A really wonderful ride, if I can just keep the dash warning lights to a min.

In advance, mucho thanks from the land o’ the Hokies!!