lambda sensors

[lefty007]

i have a z4 on a 55 plate. it failed mot due to emissions. i was told it was the lambda sensors i took it to a local garage where they did a diagnostic test it only picked up two sensors and said they were ok. i am now told there are four sensors how do i know which one is at fault.

 

[Mr Tidy]

Hi and welcome by the way.

I would try to find a BMW Specialist as they will be more familiar with Z4s, and may have more specific diagnostic equipment - plus it will be much cheaper than using a main dealer!

If you give an idea of where you are, I'm sure someone will be able to give recommendations.

 

[lefty007]

i live in newcastle-upon-tyne thanks

 

[lefty007]

bank1 sensor2 on a z4 2.o roadster any one know where it is situated

 

[lefty007]

i have found it is a bank1 sensor2 lambda but where is it ?

 

[LittleZ4]

I really want to say post cat coming off the manifold for cylinders 1-3??
Happy to be corrected

 

[lefty007]

it is a 2litre 4 cylinder roadster

 

[rsrider]

Think you might want to re-read forum rules and put this in the right section as well.

 

[Trav]

https://z4-forum.com/forum/viewtopic.php?t=21232

Similar thread I think. Good luck.

 

[LittleZ4]

Ah we probably should have asked what engine it was first!!

 

[lefty007]

you are right it is post cat sensor £112 plus labour

 

[lefty007]

looking for a catalylic converter for z4 e85 2.0l roadster

 

[ph001]

looking for a catalylic converter for z4 e85 2.0l roadster

...in which case you are actually asking for an entire exhaust manifold as the cats are built into them.

 

[lefty007]

I have replaced the upstream and downstream lambda sensors now I find there’s a fourth one anyone know what it’s called and what does it do thanks

 

[Nanu]

If you need a Indy in the Newcastle area try Plough Motors at Boldon. Have used him several times and has changed my sensors

 

[mac27040]

i would check manifold as the 2.0 tends to crack them, this could be giving the lambda sensor wrong mixture signals !!