Overview of the new EA288 series diesel engines1.6 to 2.0 litres displacement. The new EA288 generation TDI engines will be available in 1.6 and 2.0 litre displacement versions. The agile four-cylinder develops 66 kW / 90 PS and 140 kW / 190 PS. Maximum torque is extremely impressive in all cases – lying between 250 and380 Newton metres.More fuel-efficient, powerful and economical. Together with the launch of the EA288 engine line-up, Volkswagen AG is raising its TDI technology – refined over the years – to new levels of sustainability. Compared to the previous EA189 series, the diesel emits up to 7 g/km less CO2; total emissions were reduced by up to 45 per cent in the Euro-6 version. Individual engines show performance gains of up to 12 per cent; in certain drivetrain configurations the improvement is as much as 26 per cent.Identical parts wherever possible. Coverage of all legal emissions levels worldwide, the implementation of two engine displacement classes and differentiation of the power range show the variability of the EA288, which is being used as the standardised diesel base engine series in the modular diesel system (MDB). The design of modular components gives engine factories the ability to react flexibly and quickly to changing market conditions and customer wishes. Many key components of the EA288 series TDI engines – such as the valve actuation module, fuel induction and exhaust gas recirculation – enable this on the emissions side due to their modular construction. Later this year, Volkswagen AG will offer a version of the EA288 engine, which already fulfils the Euro-6 standard and will apply to all new vehicles, but will not go into effect until September 2014.Technical details of the new EA288 series diesel enginesExcept for the cylinder spacing and stroke/bore ratio, everything else is new. Just like the new petrol engines (EA211), with the introduction of the modular transverse matrix, the only dimension of the new four- cylinder diesel that is the same as that of the previous model is the cylinder spacing.Internal engine modifications to reduce emissions. Emissions- relevant components are either implemented in modular construction to conform to the specific emissions standard, or they are prepared in the mechanical design of subassemblies, such as fuel injection, cylinder pressure sensor, turbocharging and intercooling within the fuel induction module. These actions make the TDI, as noted, fit for the upcoming Euro-6 emissions standard today; in addition, they enable compact construction. Compliance with the Euro-6 standard is already built in: the standard requires a further reduction in nitrogen oxides (NOx) in the exhaust stream from 180 to 80 mg/km in diesel engines. Three different types of exhaust gas recirculation (EGR) are used, depending on emissions requirements:• Cooled high-pressure EGR without low-pressure EGR.• Cooled low-pressure EGR without high-pressure EGR.• Cooled low-pressure EGR and uncooled high-pressure EGR.Complex emissions control. Just like the internal engine modifications, the emissions control components are modularly constructed. In the MDB, the arrangement of these components close to the engine is new. To fulfil various emissions standards around the world, the following emissions control components are used either individually or in combination:• Oxidation catalytic converter• Diesel particulate filter• NOx storage catalytic converter or selective catalytic reduction system (SCR)For vehicles up to the Golf class, a NOx storage catalytic converter handles the main reduction in NOx emissions. Meanwhile, in larger and therefore heavier models, Volkswagen utilises SCR (Selective Catalytic Reduction) technology with AdBlue injection, such as is used today in the new Volkswagen CC BlueTDI. Various other design modifications optimise fuel economy and comfort as well:Low-friction bearings and two-stage oil pump reduce friction. Along with reducing hazardous emissions, Volkswagen has tuned all sub- assemblies of the new TDI for minimal internal friction. These actions include piston rings with less pre-tension, improved rib cooling between the cylinders and the use of low-friction bearings for the camshaft (drive-side) and the balancer shafts. In the oil circulation loop, energy balance was optimised by a two-stage oil pump with volumetric flow control, depending on power demand.Quickly up to temperature. An innovative thermal management system implements separate cooling circulation loops for the cylinder head and the cylinder crankcase during the hot operating phase. This allows the engine to heat up to its operating temperature faster. A pleasant side effect: the interior also gets warmer quicker in the winter. Another independently controlled cooling loop enables optimal regulation of charge air temperature with additional emissions control benefits.Balancer shafts for the 2.0 TDI. The new diesels are not only very low in emissions, fuel-efficient and torque strong, they are also very smooth- running and comfortable. Consider the 2.0 TDI: two low-friction bearings are used in its balancer shafts. They eliminate free inertial forces that occur in any piston engine system. Having a positive effect on acoustic comfort are the toothed belt drive of the oil and vacuum pumps operating in the oil sump and the encapsulated injection nozzles.
