o2 sensor service

[Kyle]

HI guys!

I have recently replaced the fuel filter on my E46 320i as most people suggested this as a cure for poor fuel economy, and it worked! :bravo:

Car is down from +- 13l/100km to around 10.9!

I've read in a few other posts that cleaning/replacing your O2 sensors could further improve economy, does anyone know where these are situated and what would be the best way to approach this job?

 

[Loom]

O2 sensors are quite pricey so I wouldn't replace them just in case... Have the codes read to see if anything O2 sensor related pops up.

On my E36 323i there are two sensors in front of the cats. You might have to unbolt the exhaust at the outlet manifold to gain access to them. Have a look at www.realoem.com to see where yours are located.

 

[Kyle]

O2 sensors are quite pricey so I wouldn't replace them just in case... Have the codes read to see if anything O2 sensor related pops up.

On my E36 323i there are two sensors in front of the cats. You might have to unbolt the exhaust at the outlet manifold to gain access to them. Have a look at www.realoem.com to see where yours are located.

Yeah these can be quite expensive, was looking more at getting them cleaned. My car has done +- 200 000kms and they havent been touched, so I think a good clean would do.

 

[Yulz9081]

Did you get them cleaned Kyle?
02 Sensors generally only cause fuel economy issues when its not reading correctly and will throw errors with the engine light on.
So if this isn't the case then you should be ok.

 

[Kyle]

Kinda lost interest in getting the car to be light on fuel :nonono:

 

[Yulz9081]

Lol acceptance is key :rollsmile: If you getting below 12 then count your blessings

Beats my 13.6

 

[Kyle]

13.6 :biglol: now i dont feel that bad

 

[AcidBurn]

13.6 :biglol: now i dont feel that bad

i get 8.7:thumbs: hope that doesnt make you feel bad:tease:

 

[Kyle]

13.6 :biglol: now i dont feel that bad

i get 8.7:thumbs: hope that doesnt make you feel bad:tease:

You must drive like a granny:rollsmile:

 

[AcidBurn]

13.6 :biglol: now i dont feel that bad

i get 8.7:thumbs: hope that doesnt make you feel bad:tease:

You must drive like a granny:rollsmile:

indeed:roflol:

 

[Iceman007]

O2 sensors do get clogged and it does make a difference if they replaced or cleaned.

This is my story
Firstly I bought my E90 LCI 325i and it had 42 000km on and all was well.
On about 54 000km if the car stood for 1hour or the next morning it would Misfire and smell fuel. MP replaced all 6 injectors and problem was solved. A few days later if I started the car in the morning it would tend to hunt in the morning. BMW did load latest software but no luck. BMW replaced Fuel filter/Pump in fuel tank and it still persisted. BMW then replaced Vanos Solenoids and hunting rpm problem still persisted in the morning. The Car was also heavy on fuel 14 to 16L/100km in town and 12L/100km on the highway 120k/h to 130km/h NOTE!!! NO FAULT CODES

PUMA case opened: :thumbs:
Replaced all 6 injectors again and problem persist. Then they replaced my O2 sensor but hunting persisted but my fuel economy went way way better 8.6 t0 8.9L/100km on highway and 12.6L/100km in town. :thumbs:
Over fuelling can clog O2 sensors or damage them and I think that is what happened to them right in the beginning. Mechanic told me they were clogged.
I received my Car today and they are going to replace the complete Head and Valvetronic,s on my Car as soon as all the Parts arrive. They suspect there is a Valve that is not closing after they did a test by manually advancing the cam to 180’ or something and the car backfires badly and it’s not normal according to the BMW REP from Joburg that was also there yesterday for the second time.
Seems like I’m getting the complete engine replaced bit by bit at the rate they are going. This has been going on for 2 months now. But they have treated me well: Given me a full tank of petrol in my Car and I had a loan F30 that was Brand New for it had 16km on its ODO :thumbs:
Gave it back with 240km on its ODO now :rollsmile:

 

[Kyle]

O2 sensors do get clogged and it does make a difference if they replaced or cleaned.

This is my story
Firstly I bought my E90 LCI 325i and it had 42 000km on and all was well.
On about 54 000km if the car stood for 1hour or the next morning it would Misfire and smell fuel. MP replaced all 6 injectors and problem was solved. A few days later if I started the car in the morning it would tend to hunt in the morning. BMW did load latest software but no luck. BMW replaced Fuel filter/Pump in fuel tank and it still persisted. BMW then replaced Vanos Solenoids and hunting rpm problem still persisted in the morning. The Car was also heavy on fuel 14 to 16L/100km in town and 12L/100km on the highway 120k/h to 130km/h NOTE!!! NO FAULT CODES

PUMA case opened: :thumbs:
Replaced all 6 injectors again and problem persist. Then they replaced my O2 sensor but hunting persisted but my fuel economy went way way better 8.6 t0 8.9L/100km on highway and 12.6L/100km in town. :thumbs:
Over fuelling can clog O2 sensors or damage them and I think that is what happened to them right in the beginning. Mechanic told me they were clogged.
I received my Car today and they are going to replace the complete Head and Valvetronic,s on my Car as soon as all the Parts arrive. They suspect there is a Valve that is not closing after they did a test by manually advancing the cam to 180’ or something and the car backfires badly and it’s not normal according to the BMW REP from Joburg that was also there yesterday for the second time.
Seems like I’m getting the complete engine replaced bit by bit at the rate they are going. This has been going on for 2 months now. But they have treated me well: Given me a full tank of petrol in my Car and I had a loan F30 that was Brand New for it had 16km on its ODO :thumbs:
Gave it back with 240km on its ODO now :rollsmile:

You might just end up with a brand new car when they're done :bravo:

The thing is, my fuel filter was fault, and as a result, the car was overfuelling. So I really think i should have a look at those sensors

 

[Iceman007]

O2 sensors do get clogged and it does make a difference if they replaced or cleaned.

This is my story
Firstly I bought my E90 LCI 325i and it had 42 000km on and all was well.
On about 54 000km if the car stood for 1hour or the next morning it would Misfire and smell fuel. MP replaced all 6 injectors and problem was solved. A few days later if I started the car in the morning it would tend to hunt in the morning. BMW did load latest software but no luck. BMW replaced Fuel filter/Pump in fuel tank and it still persisted. BMW then replaced Vanos Solenoids and hunting rpm problem still persisted in the morning. The Car was also heavy on fuel 14 to 16L/100km in town and 12L/100km on the highway 120k/h to 130km/h NOTE!!! NO FAULT CODES

PUMA case opened: :thumbs:
Replaced all 6 injectors again and problem persist. Then they replaced my O2 sensor but hunting persisted but my fuel economy went way way better 8.6 t0 8.9L/100km on highway and 12.6L/100km in town. :thumbs:
Over fuelling can clog O2 sensors or damage them and I think that is what happened to them right in the beginning. Mechanic told me they were clogged.
I received my Car today and they are going to replace the complete Head and Valvetronic,s on my Car as soon as all the Parts arrive. They suspect there is a Valve that is not closing after they did a test by manually advancing the cam to 180’ or something and the car backfires badly and it’s not normal according to the BMW REP from Joburg that was also there yesterday for the second time.
Seems like I’m getting the complete engine replaced bit by bit at the rate they are going. This has been going on for 2 months now. But they have treated me well: Given me a full tank of petrol in my Car and I had a loan F30 that was Brand New for it had 16km on its ODO :thumbs:
Gave it back with 240km on its ODO now :rollsmile:

You might just end up with a brand new car when they're done :bravo:

The thing is, my fuel filter was fault, and as a result, the car was overfuelling. So I really think i should have a look at those sensors

I know the e46 fuel filter for the 6cylinder models has a pressure regulator built in to the filter and if its fualty you will have problems. mine on my e46 was replaced because it caused the car to stall sometimes. After I replaced it on my e46 the problem was solved. The E90 has a complete differant setup and very expensive.