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Before you buy a used Audi A6 (C6).

2004–2011 · Petrol / Diesel · 5 engines

Taken only from Testigo's sourced sheets. Use it to question the seller and on the test drive: it does not confirm that any particular car is affected.

Audi A6 (C6), real photo of this generation
M 93 · CC BY-SA 3.0 DE · Wikimedia Commons · Photo source

The essentials.

Typical faults by engine

The period and mileage are those mentioned by each sheet's sources. They are not a maintenance interval and do not predict that any particular car will fail.

All versions

Sheets the catalogue links to all 5 of its engines.

  • A/C not cooling: N280 valveClimate control
    Period mentioned
    2006–2026
    Mileage mentioned
    The sheet does not mention a mileage.

    Applies if: Only if fitted with the air conditioning system described.

  • Audi Multitronic (CVT) gearboxAutomatic gearbox
    Period mentioned
    2000–2014
    Mileage mentioned
    The sheet does not mention a mileage.

    Applies if: Only if fitted with the automatic gearbox described in the record.

2.0 TFSI

Petrol

2.0 TDI

Diesel

2.7 / 3.0 TDI V6

Diesel

S6 (5.2 FSI V10) · RS6 (5.0 TFSI V10)

Petrol

We have no faults specific to this engine, only those common to every version.

Which engine has the fewest documented faults?

Documented faults and recalls by engine for the Audi A6 (C6)
EngineDocumented faultsRecalls
2.0 TFSIPetrol32 with conditions0
2.0 TDIDiesel32 with conditions0
2.7 / 3.0 TDI V6Diesel32 with conditions0
S6 (5.2 FSI V10)PetrolFewest documented22 with conditions1
RS6 (5.0 TFSI V10)PetrolFewest documented22 with conditions1

According to the data we have, the engines with the fewest documented faults are: S6 (5.2 FSI V10) (Petrol), RS6 (5.0 TFSI V10) (Petrol).

By fuel type, the one with the fewest documented faults is: Petrol.

We only count the sourced sheets we have. An engine with fewer is not guaranteed to be more reliable: it may have been studied less or sold in smaller numbers.

Official recalls: ask before you pay

A recall existing does not mean this car is affected or that it is still outstanding: it depends on the chassis number, the market and the production date.

  1. Ask the seller for the chassis number (VIN): it has 17 characters, appears in the car's documents and can usually also be seen at the base of the windscreen.
  2. Ask an official Audi dealer, or the brand's official website if it lets you check by chassis number, whether each recall has been done or is still outstanding for that VIN.
  3. Manufacturer recalls are normally carried out free of charge by the official service network. If one is outstanding, ask for it to be done before you close the sale.
Airbag inflator deterioration due to moisturePassive safety

Engines: S6 (5.2 FSI V10) (Petrol)

How to check it: Check VIN; replace the inflator or module specified by the recall.

View full entry
LED positioning light out from contact corrosionLighting

Engines: RS6 (5.0 TFSI V10) (Petrol)

How to check it: Check dates of both headlights; replace affected units with modified ones.

View full entry

On the test drive: what to look and listen for

Taken from each sheet's symptoms and checks. You can tick off what you have already looked at: it is saved only in this browser.

0 of 5 checked

Injection / high-pressure pump

  • Look out for: Power loss or hesitation at full load, fuel pressure codes, high-pressure pump noise; fuel smell in the oil and a rising level if the pump leaks; misfires.

    Ask them to check: Check the high-pressure pump follower at every service, smell the oil and watch its level, and read fuel pressure with a diagnostic tool.

Injection / cylinder head

  • Look out for: Growing noise from the cylinder head, power loss and rough running (cams and lifters); unstable idle, smoke or hesitation (injectors); on the 16-valve 2.0 TDI, coolant loss with no visible leak from a cracked head.

    Ask them to check: Check the oil history (VW 505.01), listen to the head, check injector balance rates with a diagnostic tool and, on the 16-valve 2.0 TDI, read the head part number (03G 103 351) and look for coolant loss.

Timing / intake / leaks

  • Look out for: Chain rattle for the first seconds after a cold start; power loss or limp mode from the intake flaps; coolant or oil loss in the engine V; EGR faults with rough idle.

    Ask them to check: Listen to a cold start (a rattle lasting more than 2–3 seconds is a bad sign), check flap operation with a diagnostic tool, look for leaks in the engine V and check the oil change history.

Climate control

  • Look out for: The air does not cool or cools intermittently (for example only at motorway speed), and sometimes the compressor rattles with the A/C on. Codes 01232 (N280 valve), P2612 or 00898.

    Ask them to check: Read the codes and N280 control current with VCDS or ODIS, measure its resistance (about 10 ohms) and check the connector and wiring before replacing parts. If the valve or compressor is replaced, the whole circuit must be flushed.

Automatic gearbox

  • Look out for: Judder or vibration when pulling away (especially uphill), a slipping feeling at low revs, jerky acceleration and limp mode with limited speed; sometimes a burning smell.

    Ask them to check: Read the gearbox codes with Audi-compatible equipment, check the fluid change history and, at a specialist, judge whether fluid and a clutch adaptation are enough or the control unit or variator needs repair. With limp mode or a burning smell, stop driving.

OBD codes worth looking for

If they let you read the fault memory with an OBD reader, these are the codes mentioned in this model's sheets:

01232P261200898

Sources

Every fact on this page comes from these Testigo sheets and their original sources. Sources are not checked in real time.

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