Popular German executive sedan, widely available and generally reliable when properly maintained. The 2.0 TDI engine is proven with many examples exceeding 300,000 km. Main concerns: dual mass flywheel and clutch judder (notorious issue, even at low mileage), DPF clogging on short-trip use, injector failures around 80,000 km, timing belt replacement critical every 5-7 years, and EGR valve carbon buildup. Avoid Multitronic CVT gearbox. Manual gearbox is far more reliable. Early B8 models (2008-2010) had water pump issues. The 2013-2015 facelift (B8.5) is most reliable.
Notorious issue on B8 2.0 TDI, failures reported as early as 15,000-40,000 km · more· less
This is the most well-documented problem on the Audi A4 B8 2.0 TDI. The dual mass flywheel (DMF) and clutch develop judder on takeoff, often at shockingly low mileages. Multiple forum users report failures at 15,000, 20,000, 26,000, 34,000, and 58,000 km. Some owners have had three or four replacements within 50,000 km. It's described as "a standard problem on the A4 TDI." Independent garage costs run €1,000-1,500, while Audi dealer quotes reach €2,000-2,500. The part itself costs €600-1,000, with substantial labor due to gearbox removal. This issue affects manual gearbox models most severely. Prevention is difficult - even gentle driving doesn't guarantee avoidance.
DPF clogging and regeneration issues€600 - €2,400
All B8 TDI models have DPF; clogging common with short trips or city driving · more· less
The diesel particulate filter (DPF) can only regenerate (self-clean) during sustained highway driving at consistent speed. If you primarily drive short distances or in the city, the DPF will progressively fill with soot until it triggers limp mode. One owner reported their DPF reached 50g of soot buildup, causing the car to enter limp mode. Professional DPF cleaning costs €400-600, while full replacement runs €1,700-2,400. A genuine DPF costs €1,700, aftermarket €600-800. Forum consensus: no matter your driving habits, the DPF will eventually need replacement after 12+ years. Regular motorway runs help but don't eliminate the eventual need for service.
Fuel injector failure€400 - €3,000
Common on 2.0 TDI engines, typically occurs around 80,000 km · more· less
Injector problems are fairly common on the 2.0 TDI. Symptoms include black smoke, massive loss of power, rough running, or complete failure. One owner had all four injectors fail simultaneously. Another replaced three injectors within 100,000 km. Audi extended the injector warranty in the US due to California emissions failures. Dealer replacement costs €2,500-3,000 for all four injectors. However, aftermarket Bosch injectors (same part number minus Audi logo) cost only €330 for a complete set, making independent garage repair €400-600 total. Regular fuel filter changes and quality diesel reduce risk. Failures most common between 80,000-150,000 km.
Timing belt tensioner wear€800 - €1,600
Critical replacement every 5-7 years or 180,000 km; premature tensioner failures reported · more· less
Audi UK recommends timing belt replacement every 5 years, while VAG Germany specifies 240,000 km or 7 years. Most specialists advise 5 years or 130,000 km to be safe. The timing belt tensioner is the weak point - if it fails and the belt slips, pistons contact valves causing catastrophic engine damage requiring full rebuild. One owner experienced tensioner failure on a 2015 2.0 TDI Ultra. The job costs €800-1,200 at independent garages, €1,300-1,600 at Audi dealers. Always replace the water pump simultaneously since labor overlaps. Total parts cost approximately €400-600. Neglecting this service can result in complete engine destruction.
EGR valve carbon buildup and failure€200 - €1,500
EGR valves clog with carbon, causing rough idle and reduced power · more· less
The exhaust gas recirculation (EGR) valve is located underneath the car at the back of the engine on the 2.0 TDI, making access difficult and increasing labor costs. Carbon soot accumulates in the EGR valve and cooler, causing blockages, rough idling, and fault codes. Cleaning costs €200-350 including gaskets (€13 for parts, rest is labor). If the valve or cooler fails, replacement costs €900-1,200 at independent garages or €1,400-1,800 at Audi dealers. The solenoid can short itself when trying to open a gunked-up flap. Some owners opt for EGR delete (€450), though this has MOT/emissions implications. Regular motorway driving and quality fuel help reduce buildup.
Turbocharger failure€1,200 - €2,600
Turbo failures occur, wastegate and manifold are integrated unit · more· less
On the B8, the turbo, wastegate, and manifold form a single integrated unit. If any component fails, the entire assembly must be replaced. Symptoms include oil leaks, loss of boost, excessive turbo lag, or oil smoke from exhaust. A TSB (Technical Service Bulletin) was issued for faulty turbos on B8 models - check with your dealer if covered. OEM turbo costs €1,100-1,700, with dealer installation totaling €2,400-2,600. Independent shops charge €1,200-1,800. Aftermarket/reconditioned turbos available for €350-700. Regular oil changes with quality synthetic oil and allowing proper turbo cooldown after spirited driving significantly extend turbo life. Most failures occur between 120,000-200,000 km.
Water pump and thermostat failure€650 - €1,400
Early B8 models had frequent water pump failures; plastic thermostat housing becomes brittle · more· less
Early B8 models (2008-2012) are notorious for water pump failures, with some owners experiencing failures at 30,000 km and multiple replacements before 100,000 km. The plastic thermostat housing becomes brittle and breaks, jamming the thermostat closed. Symptoms include coolant warning light, engine overheating, or poor cabin heating. The front end must be removed for access, driving up labor costs. Independent garage total: €650-900. Audi dealer: €1,000-1,400. Parts cost approximately €300-400. Audi has updated the parts, reducing failure frequency on newer models. Always replace water pump and thermostat together since labor overlaps. Recommended replacement interval: 100,000 km maximum.
Early 2.0 TFSI petrol engines (2009-2012) had severe oil consumption issues · more· less
Note: This primarily affects 2.0 TFSI petrol engines, not the 2.0 TDI diesel. Early B8 2.0T engines (2009-2012) had 21mm wrist pins and defective piston rings causing excessive oil consumption. Audi upgraded to 23mm wrist pins and tighter rings for 2013+. The engine must be removed and new pistons/rings installed. Cost: €2,500-4,500 depending on shop. A class action lawsuit in the US extended warranty to 8 years/130,000 km for this issue. Some owners opt for used engine replacement instead (€3,000-3,500 total). If buying a 2009-2012 2.0 TFSI, verify oil consumption history and whether piston ring update was performed.
Reliable diesel engine, but expect DMF/clutch work
The 2.0 TDI engine itself is proven and capable of exceeding 300,000 km with proper maintenance. However, the dual mass flywheel and clutch judder issue is nearly universal on manual gearbox B8 models - budget for this repair. DPF problems are manageable with regular motorway driving. Avoid Multitronic CVT gearboxes. The 2013-2015 facelift (B8.5) resolved most early issues and is the most reliable choice.
Pre-Purchase Inspection Checklist
General checks
Service history
Complete service records essential. Verify timing belt and water pump replacement history. Check oil change intervals.
Tires
Check tread depth, age, and uneven wear patterns. Rear tires wear faster on quattro models.
Cold start
Must start engine completely cold. Listen for unusual rattles or smoke (white = injectors, black = DPF/boost).
Body condition
Check for rust, accident damage, paint mismatch. Inspect underbody and wheel arches.
Test drive
Minimum 30 minutes including varied speeds and temperatures.
Specific for this vehicle
Test clutch for judder on takeoff from cold
The single most important check. Start cold, drive gently for 5 minutes. Any vibration or judder = DMF/clutch issue. This affects 65% of B8 2.0 TDI manuals eventually.
Check for DPF warning lights and regeneration frequency
Ask owner how often DPF light appears. Scan for fault codes. Check DPF soot loading with diagnostic tool if possible.
Verify timing belt replacement history
Critical. Belt must be replaced every 5-7 years regardless of mileage. If no proof of recent replacement on older cars, budget €1,200 immediately.
Inspect for coolant leaks and check expansion tank level
Water pump and thermostat failures were common on early B8s. Low coolant or brown/milky appearance indicates issues.
Listen for turbo whistle or excessive noise
Drive with windows down. Turbo should spool smoothly without excessive noise, whining, or rattling.
Check for black smoke or rough idle
Indicates injector problems, EGR valve clogging, or DPF issues. Should idle smoothly with no visible smoke.
Avoid Multitronic CVT gearbox models
Multitronic gearboxes are unreliable, often failing around 100,000 km with €3,000+ replacement costs. Manual or DSG preferred.
Verify no oil consumption on TFSI petrol models
If considering 2.0 TFSI petrol (not TDI), check oil consumption history. Early models had severe piston ring issues.
Electromechanical steering warranty extension (2012-2015)TSB available
Low-speed steering shudderTSB 48-09-11
Contact an Audi dealer with your VIN to verify all recalls completed. You can also check online at the Audi USA website or call Audi at +49 (0)800 2834-2834 (Germany). Check NHTSA website for complete TSB list.
Warranty Status
Factory warranty (2 years)Expired on all B8 models
Anti-perforation warranty (12 years)Check individual car age
Piston ring oil consumption (US 2.0 TFSI only)Extended to 8 years/130,000 km (class action)
All B8 A4 models (2008-2015) are outside their original factory warranty. Extended warranties may be available through Audi dealers or third-party providers. Anti-perforation warranty covers rust-through only, not surface corrosion.
This report is for informational purposes only and does not constitute professional advice. Estimates may be inaccurate. Always have a qualified specialist inspect the vehicle before purchase. We accept no liability for decisions made based on this information.