Audi check engine light – diagnostic – service and repair

Audi A6 “check engine” light service

This Service page instructions guide describes how to service and repair Check Engine Light issue on Audi A6 models and can be used for:


Audi A6 2.7 – 3.0 TDI released from 2004 to 2008 with V6 engines but it might be also applied on other Audi engine configuration models that have similar engine intake systems and engine setups, like Audi A3 – A4, – A5 – A8 – Q3 and Audi Q5 – V6 and V8 engines.

If you have a diagnostic device or OBD you might receive the following errors:

Swirl Flap Intake manifold OBD Fault Codes: P0171P1018P1518P3135P2004P2008Audi A6 2.7 – 3.0 TDI 2004 – 2008P2011P2015 – intake manifold runner (bank 1 or 2) lower limit not reached error.

If you don’t have a diagnostic device  the check engine will light up in your gauge dashboard. Most common cause of this problem are the intake Banks that are defective or not working.

For this procedure you will need the Audi A6 2.7 – 3.0 TDI 2004 – 2008 swirl flap, intake manifold repair kit mounting:

Possible causes, diagnose and fixing:

Step 1 – Broken intake actuator or warn – Slow intake actuator MOTOR rotation. Once contact car key is inserted in cotact and turned in ON — In The normal driving position, intake actuator motors knobs will go up and down.Audi A6 Engine Control Unit (ECU)

If any of the two motors is slower than the other one, than intake manifold left or right runner (bank 1 or 2) is warn or broken

Manual diagnose:
– Release runner connection from both intake actuator motors and redo test procedure.
If the intake actuator motors turning speed are different – than the slower actuator motor is broken = Replace Actuator Motor.

If the intake actuator motors are turning at the speed, with runner connection off , than actuator motors are OK and you can Go to Step 2.

Step 2 – Intake manifold left or right runner BANK or SWIRL FLAP (1 or 2) is warn or broken (Once contact key is inserted and turned in ON position — In The normal driving position, intake actuator motors knobs will go up and down).
If Intake actuator motors turning speed are the same, with runner connections on then
Manual diagnose:
– Unmount  runner bank block off the engine and inspect swirl flaps and flap supports for wearing signs

Check if there is any vertical or horizontal movement in flaps axles or if flaps supports are oval or warn.
– Check for parts or points that are jamming flap rotation, wile mounted on bank case
– Check for clogged holes or has carbon buildup deposits.Audi A6 Check Engine Light Error repair kit


Dew to the severe wear of “bank1” and “bank2” swirl flap manifolds found in 2.7 TDI and 3.0 TDI engines, control units will detect malfunctions accompanied with dashboard errors. As a result your vehicle will not function up to the OEM parameters.
Among most common side effects are: higher consumption and CO2 levels, uneven idle RPM’s, impaired acceleration and de-acceleration.
For Automatic Transmission models Cruise Control will struggle to maintain speed resulting in harder gear changes and low torque power.


In case you service or replace swirl flaps with an new kit make sure that swirl flaps supports are inserted in the right position ( and not the opposite or wrong way!!!), many technicians are making this mistake resulting in  swirl flap rotation jam.

We also advice you checking that general

Audi general intake connection

intake connection is not clogged by carbon buildup deposit.

More about : Audi service – Audi A6 check engine light – Audi service – Audi manuals – Audi do it your self – Audi help – Audi guide – Audi intake removal – intake manifold flap motor – intake actuator V157, V275 – Diagnostic Trouble Code (DTC) – Engine Control Unit (ECU) – Level 1 OBD-II scanner – Engine light ON – VDO motor

Share this Post