Engine codes advisory on MOT 2.7T Petrol

[StuC]

Hey all,

We have a 2.7T V6 Petrol A6 Avant which has been throwing up some codes that I would really appreciate some help with.
Here are the codes as taken from the printout from the garage...

P1459 Exhaust gas temperature sensor 2 signal improbable.

P1136 Additive mixture adaptation for air (Bank 1 sensor 2) System too lean.

P1138 Additive mixture adaptation for air (Bank 2 ) System too lean.

P0300 Combustion failure detected faulty (which I think should actually read 'Random/Multiple Cylinder Misfire detected)

P0306 Combustion failure detected cylinder 6 faulty

P0302 Combustion failure detected cylinder 2 faulty

I have tried to look up the first 3 codes here...
OBD II Fault Codes

The 3 top codes don't seem to correspond with the descriptions on this site. Is that right?

We had initially thought that the issue was the O2 sensor/s.
After doing some reading on here, it would appear that it could simply be the fuel type, as we have been using 97RON rather than 99.
Alternatively would the injectors be worth looking at ahead of the O2 sensors?

Any input would be greatly appreciated.
Stu

 

[ex911driver]

coil packs?
try some injector cleaner or octane booster through it.

 

[StuC]

Are you thinking coil packs because of the combustion failure?

 

[Administrators]

I would be looking to change the EGT and the airmass. The EGT are a common problem and the airmass will give you the lean running. Clear the codes and see how it goes from there. I wouldn't do anything else untill those were done.

A

16684

P0300

[h=6]Random/Multiple Cylinder Misfire Detected[/h]

16686	P0302	[h=6]Cyl.2 Misfire Detected[/h]
16690	P0306	[h=6]Cyl.6 Misfire Detected[/h]

17867

P1459

[h=6]Exhaust gas temperature sensor 2 range/performance[/h]

17544	P1136	[h=6]Long Term Fuel Trim Add.Fuel,Bank1 System too Lean[/h]
17546	P1138	[h=6]Long Term Fuel Trim Add.Fuel,Bank2 System too Lean[/h]

 

[StuC]

Thanks for the reply.
The codes were cleared on Friday and the EML has not come on again since. When is was last reset it came on again the next day, so not much in the way of consistency.

EGT = Exhaust gas temperature, yes?
Am I right in saying that they are sensors between the downpipe and the turbo? (from other posts)

 

[Administrators]

Hi StuC

The EGT is on the other side of the turbo and bolts into the manifold flange of the turbo. They have to be fitted from above.



Best of luck

A