Engine Audi BAU

The 2.5-liter Audi BAU 2.5 TDI diesel engine was assembled by the company from 2003 to 2005 and belonged to the updated B-series, that is, the timing rockers are equipped with special rollers. This unit was most often found under the hood of such popular models as the A4 B6 and A6 C5.

The EA330 series also includes: AFB, AKE, AKN, AYM, BAU, BDG, BDH.


Production years 2003-2005
Displacement, cc 2496
Fuel system direct injection
Power output, hp 180
Torque output, Nm 370
Cylinder block cast iron V6
Block head aluminum 24v
Cylinder bore, mm 78.3
Piston stroke, mm 86.4
Compression ratio 18.5
Features 2 x DOHC
Hydraulic lifters yes
Timing drive belt
Phase regulator no
Turbocharging VGT
Recommended engine oil 5W-30
Engine oil capacity, liter 6.0
Fuel type diesel
Euro standards EURO 3
Fuel consumption, L/100 km (for Audi A6 2004)
— city
— highway
— combined
Engine lifespan, km ~300 000

The engine was installed on:

  • Audi A4 B6 (8E) in 2003 – 2004;
  • Audi A6 C5 (4B) in 2003 – 2005;
  • Volkswagen Passat B5 (3B) in 2003 – 2005.

Disadvantages of the Audi BAU engine

  • Most engine problems are related to failures of the electronically controlled injection pump VP44;
  • There are many cases on the net when newfangled hollow camshafts burst;
  • Also, this motor is extremely prone to oil leaks, especially from under the valve cover;
  • At high mileage, the geometry of the turbine or the viscous coupling bearing often wedges;
  • Bad oil quickly damages hydraulic lifters and pressure reducing valves.

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