Help me~ CEL 27C6 is driving me crazy.

[maicol76]

Hello guys~

plz help me~

I have been suffering from CEL 27C6 for 2~3 months.

<My mod>

SAP removal
Akra Evo
Stock map + CEL suppresed ( because of 1st cats & sap)
Map was A company's but, I channged it to B company.
Then, I changed Stock map + CEL suppresed received from B company.


Every time this error code came up, I changed related parts.
Now all O2 sensors, injectors, spark plugs, exhaust manifold gasket rings and rear fuel pumps(L & R) are new.

I checked intake & exhaust manifold, fuel line and etc for leak several times, but all ok. O2 sensor connectors are all perfect.

After I erased CEL 27C6, then the code came back again after 40~60miles driving.
But, the car runs very well.

If one throttle actuator is not good condition or fuel pressure sensor is not good condition, is it possible to happen this?
When I hold the accel pedal down, I can see little movement on only bank2 throttle actuator.
But, there are no DTC about throttle actuator and fuel pressure sensor.

This code is driving me crazy.

plz Help me~

[Dave07997S]

Check for an exhaust leak...this is a possible lean fuel mix code as well.

Dave

[maicol76]

Originally Posted by Dave07997S

Check for an exhaust leak...this is a possible lean fuel mix code as well.

Dave

As I wrote, already checked.

[M3 Number 86]

did you check the lambda sensors on the correct side? R for right?

[schnell1982]

27C6 - P2096
Information saved in
DME
Fault code
27C6 - P2096
Fault text
Oxygen sensor, adaptation, trim control, bank 1
Fault description
Post Catalyst Fuel Trim System Too Lean (Bank 1)
Condition for fault identification
Test condition:
Adaptation value reaches MIN limit and hangs in this
position
Terminal condition: Engine running
Voltage condition:
none
Condition for fault memory entry
Counter for recognition at adaptation limit >= (2x)
K_LA_TRIM_DIAG_I_AD_MAX_SCHW

Action in service
1. Check the fuel system and the exhaust system for leaks
2. Check pre-cat and post-cat sensors and replace as
indicated
Fault effect and breakdown warning
MIL on after engine runs 2x


27C6 - P2097
Information saved in
DME
Fault code
27C6 - P2097
Fault text
Oxygen sensor, adaptation, trim control, bank 1
Fault description
Post Catalyst Fuel Trim System Too Rich (Bank 1)
Condition for fault identification
Test condition:
Adaptation value reaches max. limit and hangs in this
position
Terminal condition: Engine running
Voltage condition:
none
Condition for fault memory entry
Counter for recognition at adaptation limit >= (2x)
K_LA_TRIM_DIAG_I_AD_MAX_SCHW

Action in service
1. Check the fuel system and the exhaust system for leaks
2. Check pre-cat and post-cat sensors and replace as
indicated
Fault effect and breakdown warning
MIL on after engine runs 2x

[schnell1982]

From reading your post, you are throwing a lot of parts at the car.
What is your diagnostic results ?
Are you or a shop using a legit diagnostic tool to monitor the oxygen sensors or fuel system ?

I had a clients E92 M3 at beginning of the year.
Installed Akra evo system which has NO rear oxygen sensor bungs.
You have to leave the sensors plugged into the electrical connector.
I kept getting fault codes after same driving period as you.
Reached out to the tuning company and come to find out, they never tuned a cat delete file for this type of exhaust.
I reached out to ESS and they have the correct file specifically for this exhaust system.
Purchased and loaded the file, fixed all the issues.

Just wanted to share my experience with you.
Hope this helps.

[maicol76]

Originally Posted by schnell1982

From reading your post, you are throwing a lot of parts at the car.
What is your diagnostic results ?
Are you or a shop using a legit diagnostic tool to monitor the oxygen sensors or fuel system ?

I had a clients E92 M3 at beginning of the year.
Installed Akra evo system which has NO rear oxygen sensor bungs.
You have to leave the sensors plugged into the electrical connector.
I kept getting fault codes after same driving period as you.
Reached out to the tuning company and come to find out, they never tuned a cat delete file for this type of exhaust.
I reached out to ESS and they have the correct file specifically for this exhaust system.
Purchased and loaded the file, fixed all the issues.

Just wanted to share my experience with you.
Hope this helps.

Thanks for your advice

My M3 has been in this mod for 4~5 years, and there has been no such problem like this. This code appeared 2~3 months ago after installing new engine.
As you wrote, I'll go to tuning company to fix this, then post the result later on.

[maicol76]

I recorded the live data of O2 sensor.

no primary cat (akra evo)
DTC is 27C6(P2096) ; meaning is fuel mixture 'lean'

plz advice me

[craftyvtec]

Maicol, did you ever get this fixed? I have same issue