[Jklad]

Does anyone have experience using replacement eom Bosch o2 sensors for front and/or rear o2's? Are they ok to use? All four cost considerably less than the same BMW branded sensors.

Thanks.

[loweredram]

they are the same ones. When I pulled off my bmw original o2 sensors they were the exact same color , markings, stamps as the bosch. If I remember correctly they don't even say bmw on the sensors. Just a cost tip if you replace the precat get 2 of the Bosch 17098 p/n it will save you some cash. 17102 is the expensive sensor the only difference is the cable length. Im running Bosch pre and post cat o2 sensors on my car not one glitch

[bigtigga01]

OEM sensors are just rebranded bosch O2s to begin with. I don't understand how they're charging so much at the dealership.

[Jklad]

Thanks for the replies, Bosch it is!

I've been looking for a DIY for this, but can't find one so I'm assuming it's not too involved.

Are both ends of the post cat sensors located right there underneath the exhaust, above the middle splash Shield by the trans?

For the front o2s, is the sensor side in the downpipe accessed from underneath the car, or are they unbolted from the top?

Thanks.

[bigtigga01]

You are correct for the post o2s. The pre o2s can be loosened from underneath and will be easier if you move the steering rack out of the way.

[Jklad]

Originally Posted by bigtigga01

You are correct for the post o2s. The pre o2s can be loosened from underneath and will be easier if you move the steering rack out of the way.

Thanks, by steering rack, do you mean the steering lines (same steering lines I moved out of the way to replace the wp/tstat), or the actual "rack" that the steering wheel attaches to? Sorry for the noob questions's....

[Jeff@TopGearSolutions]

Steering rack is nearest downpipes and o2 sensors. He means rack. It's just 2 bolts. Nothing crazy.

[Shadow007]

I've been looking at replacing my o2 sensors with the bosch sensors, as well. I've been getting two pre cat errors for awhile now, which also contributes to my sh##ty ~15 mpg. Would it be safe to just replace those two or would I need to replace all four? I'm currently trying to get a custom tune, but I'm having maxed out afr using the BB race backend flash, compared to the pump flash.

[mweisdorfer]

The way I understand it, Bosch is the OEM supplier for such items just like they make the coils and spark plugs.

You can save a lot of money by buying the universal O2 sensor, but I have read you should only use them for post cat. You will have to cut and splice some wires.

Bosch 15733

Also, you may want to invest a $100.00 into a gadget that can test them. No sense replacing a sensor that is good.

GTC ST05 Oxygen Sensor Tester and Simulator