So, it will be goodbye for Volkswagen’s 1.5-liter TDI engine that was intended to replace the carmaker’s current 1.6-liter TDI unit. This comes as the German carmaker has decided not to continue the development of a replacement diesel unit that could have made its debut in the new generation of the VW Polo.
This was revealed by Frank Welsch, the chief of research and development at VW, to Autocar during a recent international media launching event for the carmaker’s new Golf in Spain. Welsch disclosed that VW is now abandoning its small diesel engine strategy due to many factors and will instead pursue a new venue to power its compact vehicles. Aside from stopping the development of its 1.5-liter TDI engine, VW is also halting its turbocharged 1.4-liter three-cylinder diesel engine. This smaller diesel engine is currently available for the present generation of the Polo.
The scrapped 1.5-liter TDI engine is an aluminum block high-pressure common rail powerplant intended to become a vital part of the German carmaker’s new small engine offensive. It will go in tandem with VW’s newly unfurled turbocharged 1.5-liter four-cylinder direct injection petrol engine that is found in the seventh-generation Golf facelift.
Welsch cited a number of reasons why the German carmaker had to scrap the new 1.5-liter TDI diesel engine. First is the high cost of engineering that needs to be done to make the engine economically viable. Welsch specifically mentioned the cost of development of an effective after-treatment system for the new diesel engine. According to VW’s r&d chief, the engine’s after-treatment system alone costs between EUR600 and EUR800 for the materials alone. He noted that the after-treatment system alone is already as costly as the engine. Thus, the entire engine system costs 25 percent of the Polo itself.
VW’s top man for its r&d efforts also disclosed to Autocar the other reasons for scrapping the 1.5-liter TDI diesel engine. For instance, Welsch said that more stringent standards for carbon dioxide (CO2) and nitrogen oxide (NOx) also played a role in the decision to abandon the development of the new 1.5-liter TDI diesel engine – and so is the declining demand for diesel powerplants in Europe’s B segment.
However, this doesn’t mean that VW would abandon its 2.0-liter TDI diesel engine. In fact, Welsch said that a new generation of the 2.0-liter TDI diesel engine would arrive within one or one-and-a-half years.
With VW’s small diesel engines now heading for the trash bin, the carmaker is now developing a new small-capacity petrol-electric hybrid system. According to Welsch, hybrid powerplants are more economical than diesel engines and are even environment-friendly enough to comply with stiff emission regulations.