[jesdan14]

This is the code I keep getting. Once it triggers the check engine light comes on and massive smoke comes out of my passenger side exhaust tip for a few min.

2C7E:
2C7E Lambda probe behind catalytic converter, trimming control
Error will cause a warning light
Error is not currently present
Test conditions have been completed
Signal or value below threshold

FREEZE FRAME INFORMATION
Event 1Odometer 96696kms 60084miles
voltage Lambda probe behind catalytic converter bank 1 0.02 V
voltage Lambda probe in front of catalytic converter bank 1 1.88 V
Lambda shifting return valve 1 0.00 -
input signal return valve 1 0.00 V

Event 2Odometer 96712kms 60094miles
voltage Lambda probe behind catalytic converter bank 1 0.06 V
voltage Lambda probe in front of catalytic converter bank 1 1.84 V
Lambda shifting return valve 1 0.00 -
input signal return valve 1 0.00 V

Event 3Odometer 96712kms 60094miles
voltage Lambda probe behind catalytic converter bank 1 0.02 V
voltage Lambda probe in front of catalytic converter bank 1 1.88 V
Lambda shifting return valve 1 0.00 -
input signal return valve 1 0.00 V

[orionredwing]

From the code, rear O2 sensor, bank 1.

I replaced my front O2 sensors. I could not tell which is bank 1 or 2, and since I was paying a mechanic to do it, I just had him replace both front ones for piece of mind.

Since then, I bought a Bentley Manual. Here is what it references:

Both pre and post catalytic O2 sensors are the same color code:
Cylinders 1-3 harness connector colored black
Cylinders 4-6 harness connector colored grey

Bank 1 is cyls 1-3
Bank 2 is cyls 4-6

So for you, replace the rear O2 sensor, harness colored black.

If I knew this before, I would've saved myself the cost of 1 O2 sensor, but it's cool for the peace of mind with no codes thrown since.

[jesdan14]

thanks.

[jesdan14]

When I called bmw for the part, they need the part number any idea what that may be? or if its the long or short one?