o2 sensors

[WERKE]

Hi,

I need to replace the O2 sensors on the primary catalyst, I did a search, I know there are 2 different (front-rear), but I'm not sure if it takes 2 of each?

REGULATING LAMBDA PROBE L= 340MM
11787537984

Lambda probe, black L= 325MM
11787539125

Thank you guy's

[metro44m3]

Originally Posted by WERKE

Hi,

I need to replace the O2 sensors on the primary catalyst, I did a search, I know there are 2 different (front-rear), but I'm not sure if it takes 2 of each?

REGULATING LAMBDA PROBE L= 340MM
11787537984

Lambda probe, black L= 325MM
11787539125

Thank you guy's

REGULATING LAMBDA PROBE = front O2 sensor

Lambda probe, black L = rear O2 sensor

Looks like the front is about $220 and rear is $210 from tischer.

[WERKE]

Originally Posted by metro44m3

REGULATING LAMBDA PROBE = front O2 sensor

Lambda probe, black L = rear O2 sensor

Looks like the front is about $220 and rear is $210 from tischer.

Yes, thank you for the clarification, but I wonder whether those two front sensors? on the ECS website, it is said it takes two


http://www.ecstuning.com/Search/11787537984/ES2628626/

[kenwelch]

Originally Posted by WERKE

Yes, thank you for the clarification, but I wonder whether those two front sensors? on the ECS website, it is said it takes two


http://www.ecstuning.com/Search/11787537984/ES2628626/

There are left bank and right bank primary sensors (up-stream before the cats). There are 4 sensors total 2 pre-cat and 2 post-cat.

The OBD II code will provide you with a "Bank 1 Sensor 1" or "Bank 2 Sensor 1" location. Sensor codes do not always mean the sensor is bad. So sensor testing or the other engine codes might point you in the right direction when trouble-shooting. How did you decide to replace the sensors?

Examples:
1. In class I have had rabbits eat the sensor wires on school lab vehicles parked outside. Sometimes you can repair the wire using good soldering methods. Sometimes they eat the wire right at the sensor creating a un-repairable sensor.

2. If you have a lean bank of cylinders the O2 sensor code might indicate there is something like a vacuum leak that replacing the sensor will not fix.

[WERKE]

Originally Posted by kenwelch

There are left bank and right bank primary sensors (up-stream before the cats). There are 4 sensors total 2 pre-cat and 2 post-cat.

The OBD II code will provide you with a "Bank 1 Sensor 1" or "Bank 2 Sensor 1" location. Sensor codes do not always mean the sensor is bad. So sensor testing or the other engine codes might point you in the right direction when trouble-shooting. How did you decide to replace the sensors?

Examples:
1. In class I have had rabbits eat the sensor wires on school lab vehicles parked outside. Sometimes you can repair the wire using good soldering methods. Sometimes they eat the wire right at the sensor creating a un-repairable sensor.

2. If you have a lean bank of cylinders the O2 sensor code might indicate there is something like a vacuum leak that replacing the sensor will not fix.

Perfect, thank you for the answer. For that is why I want to replace the o2 sensors is that someone on the forum told me to fix a problem with my M3 at low speed (-1500rpm) when I jump on the gas pedal, the car takes some time to react, as if the car hesitated a moment before accelerating. Also, past 6000 rpm, it seems that the strength of the acceleration is less than before, as if to 6000 rpm it had reached its maximum power..someone has suggested that I replace the o2 sensors on the primary catalysts and also replace the spark plugs.

Input is welcome.

[kenwelch]

Originally Posted by WERKE

Perfect, thank you for the answer. For that is why I want to replace the o2 sensors is that someone on the forum told me to fix a problem with my M3 at low speed (-1500rpm) when I jump on the gas pedal, the car takes some time to react, as if the car hesitated a moment before accelerating. Also, past 6000 rpm, it seems that the strength of the acceleration is less than before, as if to 6000 rpm it had reached its maximum power..someone has suggested that I replace the o2 sensors on the primary catalysts and also replace the spark plugs.

Input is welcome.

The problem you are describing will not be corrected by replacing the O2 sensors. From your description you do not have a check engine light or codes indicating O2 faults. Changing the O2 sensors will make your wallet thinner giving you the feeling that you have fixed the problem....it's a brain tease.

Your description could be misfire on acceleration.
The spark plugs might be the cause of power loss on acceleration and during higher rpm. It could be one spark plug or more, but without diagnostic equipment you will just be experimenting with parts. There are other ignition parts that could be faulty also, so the spark plug change won't cure the problem. The voltage required to fire the spark plug on acceleration increases so this can be related to plugs, coils, coil to plug connector insulation (in old cars the plug wires). Because the spark plugs wear out and are the less expensive part they of get changed when looking for an easy cure. The BMW labor for installation on the M3 doesn't make this an easy decision (about 2 hrs. or $300 labor and about $200 parts at dealer price). If you will be changing spark plugs and have the skill / knowledge then trying spark plugs is an easier choice as a test. There are a few related spark plug threads here to review that might help you with the why and how issues also suggestions for locating spark plugs.

[WERKE]

Originally Posted by kenwelch

The problem you are describing will not be corrected by replacing the O2 sensors. From your description you do not have a check engine light or codes indicating O2 faults. Changing the O2 sensors will make your wallet thinner giving you the feeling that you have fixed the problem....it's a brain tease.

Your description could be misfire on acceleration.
The spark plugs might be the cause of power loss on acceleration and during higher rpm. It could be one spark plug or more, but without diagnostic equipment you will just be experimenting with parts. There are other ignition parts that could be faulty also, so the spark plug change won't cure the problem. The voltage required to fire the spark plug on acceleration increases so this can be related to plugs, coils, coil to plug connector insulation (in old cars the plug wires). Because the spark plugs wear out and are the less expensive part they of get changed when looking for an easy cure. The BMW labor for installation on the M3 doesn't make this an easy decision (about 2 hrs. or $300 labor and about $200 parts at dealer price). If you will be changing spark plugs and have the skill / knowledge then trying spark plugs is an easier choice as a test. There are a few related spark plug threads here to review that might help you with the why and how issues also suggestions for locating spark plugs.

Ok, thank you for your suggestion man; i will replace the plugs in first. Hope this cure the problem.