EA837 or Audi V6 engines

A series of 6-cylinder V-engines Audi EA837 has been produced by the company since 2004 and is installed on almost all models of the concern: from the compact A4 to the Q7 crossovers. These engines are divided into four generations, differing in the type of injection and the presence of turbocharging.

EA837 2.4 MPI and 3.2 FSI engines

In 2004, the engines of the EA835 family were replaced by new power units of the EA837 series. The first generation engine line received a silumin cylinder block already without liners and a very complex timing drive: four chains, two intermediate gears and a balance shaft. All camshafts had phase regulators, and the intake manifold had two sets of dampers at once.

The line consisted of a 2.4-liter engine with conventional injection and 3.2-liter engines with direct injection:

• BDW (distributed injection, 177 hp / 230 Nm);
• AUK (direct injection, 256 hp / 330 Nm);
• BKH (direct injection, 256 hp / 330 Nm);
• BPK (direct injection, 260 hp / 330 Nm);
• BYU (direct injection, 249 hp / 330 Nm).

EA837 2.8 and 3.2 FSI engines

Already in 2006, the production of power units of the second generation of the EA837 family began. The difference between the new engines was the aluminum block and the AVS valve control system. Defective timing chain tensioners were upgraded, their reliability increased slightly.

The updated series consisted only of engines with direct fuel injection of 2.8 and 3.2 liters:

• BDX (direct injection, 210 hp / 280 Nm);
• CCDA (direct injection, 190 hp / 280 Nm);
• CCEA (direct injection, 220 hp / 280 Nm);
• CHVA (direct injection, 204 hp / 280 Nm);
• CALA (direct injection, 265 hp / 330 Nm);
• CALB (direct injection, 270 hp / 330 Nm).

EA837 3.0 TFSI engines

In 2008, the third generation of V6 engines debuted on the restyled version of the A6 model. These units, in addition to direct fuel injection, received turbocharging in the form of an Eaton compressor. The aluminum block, cylinder head and timing chain drive have been redesigned for more power. The control here is carried out by the Siemens Simos 8 ECU, the Hitachi injection pump of the HDP 3 type is used.

Thanks to the adjustment of the degree of boost, many modifications of such engines were created:

• CAJA (direct injection, 290 hp / 420 Nm);
• CAKA (direct injection, 333 hp / 440 Nm);
• CGWA (direct injection, 290 hp / 420 Nm);
• CGWB (direct injection, 300 hp / 440 Nm);
• CGWC (direct injection, 333 hp / 440 Nm);
• CGWD (direct injection, 310 hp / 440 Nm);
• CMUA (direct injection, 272 hp / 400 Nm);
• CTVA (direct injection, 272 hp / 400 Nm);
• CTUC (direct injection, 272 hp / 400 Nm);
• CTUD (direct injection, 354 hp / 470 Nm);
• CTWA (direct injection, 333 hp / 440 Nm);
• CTWB (direct injection, 272 hp / 400 Nm).

Engines EA837 EVO 3.0 TFSI

In 2013, Audi 3.0 TFSI Gen2 engines or the fourth generation of V6 engines appeared. The difference between the new engines was the replacement of direct fuel injection with a combined MPI + FSI. Phase regulators also appeared at the exhaust, and not just at the intake, like their predecessors; and the cylinder block, cylinder head and connecting rod and piston group were revised to increase the compression ratio from 10.5 to 10.8.

• CREA (MPI + FSI, 310 hp / 440 Nm);
• CREC (MPI + FSI, 333 hp / 440 Nm);
• CRED (MPI + FSI, 272 hp / 400 Nm).

In 2016, the latest turbocharged V6 units of the EA839 family were introduced and they gradually replaced the EA837 units, which are now installed only on Q7 crossovers.