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O2 sensor help

Discuss problems you have had or are having with your Z4
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StatusDenied
Newbie
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Posts: 18
Joined: Wed Feb 24, 2021 12:24 pm

O2 sensor help

Post by StatusDenied » Mon Feb 12, 2024 2:55 pm

Replaced the post cat as I had a ton of errors and one had no voltage at all. Did them as a pair.

However since my fuel economy has dropped considerably.

No idea how to reset adaptions? Is it even necessary?

Also not sure if my pre cat are great. Help needed!

Pre cat

https://youtu.be/7uszndF4RIY?feature=shared

Post cat

https://youtube.com/shorts/HlVS8mdxS20?feature=shared

Fuel trims are max 5% either side.

Anything I'm missing? It seems one of pre cat sensors is definitely slower at changing.

Thanks all

Mike6
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O2 sensor help

Post by Mike6 » Mon Feb 12, 2024 7:03 pm

No expert myself but recently had my post cat sensors changed. Presumably you replaced the sensors with proper Bosch ones and werent tempted by those cheaper universal ones where you have to cut and join cables. They should just be fit and go without the need to reset anything other than the codes themselves

StatusDenied
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O2 sensor help

Post by StatusDenied » Mon Feb 12, 2024 7:48 pm

Not bosch, ngk and denso I think. But the voltages seem fine?

Mike6
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Senior Member
Posts: 1074
Joined: Thu Aug 20, 2015 1:17 pm

O2 sensor help

Post by Mike6 » Tue Feb 13, 2024 7:01 pm

OK, reasonable makes but Bosch are the recommended ones. Have you reset codes , and have any reappeared. Double check that the sensor you have are correct ones for your car, there are thousands of different ones.

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