Before you buy a used Audi A6 (C5).
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.
The essentials.
- 2 documented, sourced faults across its 5 engines.
- That is not much data: if no other faults show up here, it does not mean it has none.
- 1 of them depends on the equipment or the production date: ask what this car has.
- 2 official recalls on record: ask for the chassis number (VIN) and confirm they have been done.
- According to the data we have, the engines with the fewest documented faults are: 1.8 T / 2.4 / 2.8 (Petrol), 2.5 TDI V6 (Diesel), S6 (4.2 V8) (Petrol), RS6 (4.2 V8 biturbo) (Petrol).
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.
- 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.
1.8 T / 2.4 / 2.8 · 2.5 TDI V6 · S6 (4.2 V8) · RS6 (4.2 V8 biturbo)
1.8 T / 2.4 / 2.8 (Petrol) · 2.5 TDI V6 (Diesel) · S6 (4.2 V8) (Petrol) · RS6 (4.2 V8 biturbo) (Petrol)
We have no faults specific to this engine, only those common to every version.
1.9 TDI
Diesel
- PD TDI camshaft, injectors and cylinder headInjection / cylinder head
- Period mentioned
- 2000–2010
- Mileage mentioned
- 120,000–200,000 km
Which engine has the fewest documented faults?
| Engine | Documented faults | Recalls |
|---|---|---|
| 1.8 T / 2.4 / 2.8PetrolFewest documented | 11 with conditions | 1 |
| 1.9 TDIDiesel | 21 with conditions | 0 |
| 2.5 TDI V6DieselFewest documented | 11 with conditions | 1 |
| S6 (4.2 V8)PetrolFewest documented | 11 with conditions | 1 |
| RS6 (4.2 V8 biturbo)PetrolFewest documented | 11 with conditions | 1 |
According to the data we have, the engines with the fewest documented faults are: 1.8 T / 2.4 / 2.8 (Petrol), 2.5 TDI V6 (Diesel), S6 (4.2 V8) (Petrol), RS6 (4.2 V8 biturbo) (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.
- 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.
- 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.
- 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.
Driver airbag function restricted by age (69CJ)Passive safety
Engines: 1.8 T / 2.4 / 2.8 (Petrol) · 2.5 TDI V6 (Diesel)
How to check it: Check VIN and replace the driver airbag inflator.
View full entryFuel leak from rollover valve nipple cracksFuel system
Engines: S6 (4.2 V8) (Petrol) · RS6 (4.2 V8 biturbo) (Petrol)
How to check it: Confirm VIN and reinforce the nipple per recall.
View full entryOn 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 2 checked
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.
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.
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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