What to Watch Out For
Comfort Locking can lock you out. If you get out of the car with the engine running and close the door it will automatically lock.
Faults in the paint of a batch of 'Quartz Grey' cars left them 'zebra zoned'. Hard to see, but worth checking carefully before taking delivery.
S4 and RS4 have three radiators, two situated in the front wings where they are vulnerable to stone damage.
"EGR and oil cooler" problem which resulted in July 2008 recall for cars with engines coded BRE can lead to total engine failure.
The ends of the rear anti roll bar are protected by a plastic sleeve which cracks and lets in water leading to rusting on the anti roll bar mounts. Costs £154 to replace + labour. Audi dealers replace it with a modified anti-roll bar that does not suffer the same problem.
Dual Mass Flywheel failure increasingly common, even on Multitronics, usually replaced no question under warranty, but obviously Audi goodwill has to get thinner as the cars get older.
Early 2.0TDIs PD 140s and PD 170s with balancer shafts have a chain drive to the oil pump and the chain drive can eventually snap. Later cars have a hexagonal shaft positive drive to the oil pump that is also a problem. Failed oil pump drives totally wreck the engines and if the car has not been 100% Audi maintained, Audi will not pay.
The oil pump is driven from a balancer shaft via a short hexagonal shaft. The peaks of this hexagonal shaft locate in six corresponding but minute grooves machined within the otherwise circular-bored oil pump drive shaft. Thus, the oil pump drive relies entirely on an interference fit of little more than 0.010" along the peaks of the hexagonal shaft. After about 50,000 miles, the shaft can round off, resulting in a totally destroyed engine and turbo, plus a bill of up to £9,000.
If the danger is known and the oil pump is removed by the garage in good time, a new replacement pump will cost over £500, plus the labour etc to remove and refit it. However, it is also possible to save the old pump and modify the drive at a fraction of the cost of a new one. Many local machine shops already have numbers of these pumps in for such rectification, the drive shaft of each having been on the point of rounding off.
The non balancer shaft BKD, AZV and BMN 2.0 engines (which found their way into the 2.0 PD Octavia, A3, Golf, and various SEATs) used a chain driven oil pump very similar, but not identical, to the old 1.9 130hp PD engine. This never seems to give any problems. It's the balancer shafts that cause the problems on the 'posher' VAG 2.0 PD diesels eg Passat, A4, Superb.
This 2.0 PD differs from the 1.9 in having twin Lanchester balancing shafts which contra-rotate at 2x crank speed. The first engines used a chain drive which was a complete disaster and the later engines a gear drive. All 2.0 PD got the geared drive towards the end of 2005.
The problem with the 2.0 PD engine is the drive from the slave balancer shaft to the oil pump, which is a piece of 6 AF hex bar which has inadequate engagement depth with the grooves in the slave shaft. It's the torsional oscillations caused by the balance shafts which destroy the oil pump coupling (the 6mm AF bit of hex) and the chain drive to the balancer shafts before the gear driven systems came out, though these still give problems with the hex key rounding.
The problem is with lack of concentricity of the drive socket into which the drive rod/hex fits. Chacking shows that all the drive sockets in the failed units were off centre by at least 0.1mm. All the replacement balancer units were dead centre and have not led to a repeat failure. Some replacement balancer units have now done 100k+ miles.
You will get this problem at some point if you have a 2.0TDi WITH balancer shafts. If your 2.0TDi does NOT have balancer shafts, you will be ok. If you fit the lastest balancer shaft/ pump assembley from VAG it will more than likely cure the problem for life as they have made the hex longer and centered it all properley.
CR engines are safe. Anything before that..Audi/VAG wont say exactly when they started to fit the units that actualy work properly.
A typical scenario: "A4 Avant, 08 plate, currently with approx 78k miles on clock. Oil pressure light began flashing, drove on to Audi garage. They have so far spent 4.5hrs labour diagnosing extent of problem, as follows: "found gear drive into balance shaft rounded, requires replacement balance shaft unit, sump, turbo, sealant and gears." Audi has offered 70% factory contribution on parts, as a gesture of goodwill. I have asked for a contribution towards labour costs (another 8+ hrs), but Audi dealership is not budging."
In Avants, wear occurs in the rear suspension bushing leading to uneven tyre wear by around 3 years old.
Increasingly common for the strainer between the sump oil and the oil bump to become blocked with coagulated oil, leading to oil starvation, lack of oil pressure and the need for a new engine.
3.0TDI V6 quattros prone to water pump failure and also prone to losing coolant from the water cooled EGR valve.
Guide to cleaning out drains here: A4/Passat scuttle drains
Spate of Multitronic ECU failures reported on 2002 - 2007 cars.
A4 2,0TDI BLB engine oil pump issue thread: http://www.audi-sport.net/vb/general-automotive-chat/86907-vag-faulty-blb-engine-thread.html
Problems with 2007, 40k mile A4 2.0TDI 170 quattro since purchase have been new steering rack under warranty, new turbo under warranty, January 2012 recall to replace injectors and now oil in the coolant.
Common for 'F125 Sensor' in Multitronics to need replacing, at a cost of around £1,500.
If the turbo fails on a high mileage diesel, then it's highly likely that the oil feed pipes to it are partially choked with carbon. Essential to replace them too or the new turbo may only last 1,000 miles.
Further report of Piezeo injector failure on 80k mile 2006 3.0 V6 TDI. Quoted £3,500, but reduced by a contribution from Audi to £2,350. Apparently, contemporary high output 2.0TDIs have the same problem.
Dealer TSB to replace current 6 pack clutch of 2.5V6TDI Multitronic with a new revised 7 part clutch as there is a known problem with the Multitronic being unable to cope with the torque of the 2.5tdi. July 2008: TDIs with BRE engine code recalled for modified EGR valves and oil coolers to be fitted.
VOSA Confirmation of Injectors Recall.
Thank you for notifying Vehicle & Operator Services Agency (VOSA) of theproblems experienced with your vehicle. I can confirm theinvestigation into this fault is now complete.
Following detailednegotiations between VOSA and the vehicle manufacturer, VW-Audi Group (VAG) has agreed to replace all the injectors originally fitted to VAG group vehicles.
If any of the original injectors has already been replaced, VAGwill reimburse customers who have paid for this work themselves even if thework was completed outside of their authorised network.
If your vehilce is within the range of vehilces affected then all fourinjectors will be replaced free of charge.
To progress repairs and/or obtain a refund you should now contact the relevant VAG Customer Service Centre. Ifnecessary, they will arrange to have your vehicle inspected at anauthorised repairer free of charge. The contact telephone number you need to ring is 0800(NNN) NNN-NNNNand ask to speak toJenny Boyd or Stefan Elliott.
VOSA will continue to work closely with the VW-Audi Group to ensure that this issue is concludedas swiftly as possible.
Thank you for taking the time to bring this matter to ourattention.
Please do not hesitate to contact me on the telephonenumber below if there are any further points you wish to discuss.
Vehicle Safety Branch
Tel: 0117(NNN) NNN-NNNNbr/>Fax: 0117(NNN) NNN-NNNN/p>
Apparently, all VAG models with the 2.0TDI engine from around 2005 fitted with Siemens peizo injectors are subject to a recall which involves replacing all the injectors FOC. Job takes around 3 hours. A short circuit within the injectors causes the fuel system to shut down and engine cuts out. Manufacturer recall to replace Siemens Piezoelectric injectors of 2006 - 2009 2.0 TDI BMN engines. All the injectors from the the 2.0 TDI PD engines that use piezoelectric Siemens injectors and Siemens ECUs are affected by this problem. The most problems are on the Passat BKD 2.0 TDI 140HP. No problem from 2009 and the introduction of the common rail 2.0 TDI engine (CEGA).