[Chrisred]

Anyone try out those Bosch o2 sensors on their N54?? I need to replace all 4 of mine. Are they easy to assemble/connect?

Cause oem ones are like triple the price....

http://www.ecstuning.com/BMW-E92-335i-N54_3.0L/Engine/Emission/

[BMJ]

Originally Posted by Chrisred

Anyone try out those Bosch o2 sensors on their N54?? I need to replace all 4 of mine. Are they easy to assemble/connect?

Cause oem ones are like triple the price....

http://www.ecstuning.com/BMW-E92-335...gine/Emission/

i would have thought Bosch are the OEM manufacture?

[benzy89]

The Bosch universal sensors are the OEM BMW sensors. The difference is that the "OEM o2 Sensors" are basically ready to just be screwed in to the DPs. The Bosch universals need to be wired to fit into the electronic terminal. IIRC, the front o2 sensor terminal gets 6 wires while the rear o2 only gets 4.

Front Sensor


Rear Sensor


Basically, if you're technically savy & know what you're doing, you can buy the universal Bosch, wire/solder it together & it's good to go.

[loweredram]

Go on the Bosch web site . I replaced mine they were a direct fit and we're identical to the factory sensors. No cutting , splicing or any other modification

[Chrisred]

Question: how do I know which o2 sensors to replace. I know it must be bank 2 since I'm getting misfires on 4,5,6 cylinders. But front or rear or both??
These are the codes:

2c6a lambda probe behind cat

2c6b lambda probe behind cat

2c7f lambda probe behind cat 2

2c32 lambda probe in front cat 2

2c31 lambda probe in front cat

29d0 29d1 29d2 misfires cyl 4,5 & 6

Btw coils and plugs have been just replaced.

[335okc]

when i looked into this, i couldn't find the bank 2 wideband sensor (pre cat). i found the other 3.

[benzy89]

Did you recently have the catless DPs installed?? It's possible (and common) that whoever did your install connected the o2 sensors to the wrong DP, which is causing the emissions codes.

It actually happened to me, the car ran awful, misfired & was useless. It's a simple mistake, but has a serious impact on how the car runs.

**Just looked -- Amazon was the best price I could find for the Bosch/BMW OEM fit for ~$100

[Chrisred]

Sensors are placed correctly. They were checked.

Funny thing is that it just started all of a sudden. I had DP fix on all this time and now CEL shows up. U think DP fix messed them up??

Back to my question: how do I know if it's front or rear or both sensors on bank 2......

[R.SaenzE90]

Good thing I
Esen this thread. I've been having problems with my e90. It was in an accident and everything sounds good engine wise just that it vibrates and it idles. The Service engine light turned on and the codes read as follows

P0010- intake camshaft position actuator circuit open
P0303-cylinder 3 misfire
P0304- cylincer 4misfire
P0305-cylincer 5 misfire
P0306- cylincer 6 misfire

Its a major head cause I don't know if it may be something major. Open for any suggestions or help please.

[mattsfeir]

I was getting fuel mixture codes and replaced the fronts with the Amazon $100 ones, plug and play, no splicing. Worked for a week the car started having more problems. Switched back to stock and was back where I started.

The thought the codes may be from the rear sensors, spliced in Bosch universal ones and got different error codes related to the rear sensors.

Ended up replacing all injectors and splicing back the stock rear sensors and all is good, no codes for the past few months. End result was the injectors were causing all the codes, I'm back on the original sensors and all is good.

I think it was James535 that posted the the OE sensors are tuned/matched to the harness or something so splicing in a new sensor won't work.

[secretsquirrel]

Originally Posted by loweredram

Go on the Bosch web site . I replaced mine they were a direct fit and we're identical to the factory sensors. No cutting , splicing or any other modification

Could you provide a direct link please? This question gets asked quite often but no one seems an easy answer other than buy the OEM ones or "get to splicing". Thanks.

[bv1]

OEM part number to Bosch part number from the Bosch catalog if anyone needs.

[JamesM3M5]

1) You cannot splice in a wideband sensor onto a different connector. The connector has a calibration resistor that is set from the factory due to manufacturing variances. The DME uses the calibration circuit. So for the 2 pre-cat O2 sensors, the ones right after the turbo in the upper part of the downpipe, you must use a complete new sensor. See THIS LINK for info: http://www.wbo2.com/lsu/lsuworks.htm

The manufacturing variation problem, which results in sensors of varying sensitivities (differing pump currents for the same Lambda), is solved by adding a calibration component. A resistor (Rcal) is laser trimmed after the sensor is constructed and tested. The laser burns away material and increases the value of the resistor until a standard Ip current is produced at a known Lambda value. If this circuit is reproduced in the controller itself then each sensor will be automatically calibrated without further calibration. Obviously, as each sensor is factory calibrated, and the calibration component is usually in the sensor connector itself, if someone removes the connector, then the sensor has become uncalibrated!

2) Bosch replacements are perfectly fine for the pre-cat widebands. If you order the correct part, the connector is the correct connector, and wire length is correct as well.

3) My parts supplier only stocks the bank 1 pre-cat sensor in Bosch. It fits N52 (both banks) and N54. The bank 2 pre-cat sensor is unique to the N54 engine cars due to wire length only. It is shorter by 200mm, and has different color sheathing (grey versus black). THIS is why it is harder to find the bank 2 pre-cat sensor. They just don't make as many.

4) DO NOT CHANGE your post-cat O2 sensors unless you have a specific fault code pertaining to signal or heater circuit on the post-cat sensors. They are regular 4-wire narrowband sensors that ONLY check cat efficiency. They do not appreciably affect the tuning or driveability of the engine. Additionally, new post-cat O2 sensors paired with old pre-cat sensors can throw false "catalyst efficiency" codes since the new post-cat sensors are fast and new, while the pre-cats are slower and older. This is common on older cars.

If you want to check your pre-cat sensors, use something to log such as a BT tool, JB, Procede, or Cobb AP. Look for a wide variance in AFRs from bank 1 to 2 on the pre-cat widebands. If they deviate by a 0.5AFR or more, replace them. Robert at Vishnu told me that Shiv's car needed new ones at 56k miles - no codes, just a bit too much variance between bank 1 and 2 measured AFR.

[Chrisred]

Wow. Good write up....

[benzy89]

Originally Posted by bv1

OEM part number to Bosch part number from the Bosch catalog if anyone needs.

+1 for the COBB + Mac (I need to get my hand on Parallels for ATR), but you're still using Limewire dude???

[bv1]

Originally Posted by benzy89

+1 for the COBB + Mac (I need to get my hand on Parallels for ATR), but you're still using Limewire dude???

Haha... caught me. Dating myself I guess. I need to clean my dock I don't limewire works any longer?

Rapidshare ftw!

[benzy89]

Haha I don't think Limewire's worked in like 3-4 yrs, now it's all torrents or HulkShare & what not (for music at least)

[loweredram]

exactly where I got my info thanks for posting.

Originally Posted by bv1

OEM part number to Bosch part number from the Bosch catalog if anyone needs.

[sickem]

Originally Posted by JamesM3M5

1) You cannot splice in a wideband sensor onto a different connector. The connector has a calibration resistor that is set from the factory due to manufacturing variances. The DME uses the calibration circuit. So for the 2 pre-cat O2 sensors, the ones right after the turbo in the upper part of the downpipe, you must use a complete new sensor. See THIS LINK for info: http://www.wbo2.com/lsu/lsuworks.htm

2) Bosch replacements are perfectly fine for the pre-cat widebands. If you order the correct part, the connector is the correct connector, and wire length is correct as well.

3) My parts supplier only stocks the bank 1 pre-cat sensor in Bosch. It fits N52 (both banks) and N54. The bank 2 pre-cat sensor is unique to the N54 engine cars due to wire length only. It is shorter by 200mm, and has different color sheathing (grey versus black). THIS is why it is harder to find the bank 2 pre-cat sensor. They just don't make as many.

4) DO NOT CHANGE your post-cat O2 sensors unless you have a specific fault code pertaining to signal or heater circuit on the post-cat sensors. They are regular 4-wire narrowband sensors that ONLY check cat efficiency. They do not appreciably affect the tuning or driveability of the engine. Additionally, new post-cat O2 sensors paired with old pre-cat sensors can throw false "catalyst efficiency" codes since the new post-cat sensors are fast and new, while the pre-cats are slower and older. This is common on older cars.

If you want to check your pre-cat sensors, use something to log such as a BT tool, JB, Procede, or Cobb AP. Look for a wide variance in AFRs from bank 1 to 2 on the pre-cat widebands. If they deviate by a 0.5AFR or more, replace them. Robert at Vishnu told me that Shiv's car needed new ones at 56k miles - no codes, just a bit too much variance between bank 1 and 2 measured AFR.

thread resurrection here! So I'm maxing fuel trims big time and getting the following codes...

11314 (lambda probe in front of cat 2, trimming control)
11371 (lambda probe behind catalytic converter, sys check)
10720/1 (fuel mixture control 1&2)

So it sounds like I need to replace all four sensors?

[JamesM3M5]

Might want to pull a log, start a new thread, and see what's going on before replacing parts. Could be weak LPFP, bad LP sender, clogged air filter, bad O2s, etc.

Also, I'd only bother replacing the rear O2s if there are specific failure codes on the rear sensors. The older they are, the less likely you are going to throw a catalyst efficiency code (fails emissions test).

[sickem]

Originally Posted by JamesM3M5

Might want to pull a log, start a new thread, and see what's going on before replacing parts. Could be weak LPFP, bad LP sender, clogged air filter, bad O2s, etc.

Also, I'd only bother replacing the rear O2s if there are specific failure codes on the rear sensors. The older they are, the less likely you are going to throw a catalyst efficiency code (fails emissions test).

roger that...

http://www.e90post.com/forums/showthread.php?t=760166