This may be old stuff to some but it sounds good to me. Reading that VW already uses it is a good sign too
BorgWarner's Pressure Sensor Glow Plug for diesel engines from BERU was designed to dramatically improve the raw emissions of diesel engines. The innovation combines the sturdy heating rod of the BERU Diesel Instant Start System (ISS) with a piezo-resistive sensor to record the rapidly changing cyclical pressure in the combustion chamber and report the data to the engine control unit. Precisely regulating the combustion process allows engine developers to compensate for inaccuracies in fuel measurement, component tolerances or different operating conditions over the life of the engine. The result is higher engine performance, greater efficiency and lower emissions.
In the future, the technology can revolutionize engine combustion control by enabling Homogenous Charge Combustion Ignition (HCCI) and other cutting-edge combustion concepts while offering designers a means to extend the possibilities of meeting emission and fuel economy standards with existing internal combustion engine technologies. Introduced on the 2009 VW Jetta powered by a 2.0-liter CR-TDI engine, the BorgWarner Pressure Sensor Glow Plug is the first technology that allows OEMs to implement closed-loop combustion control in a mass-produced vehicle at a reasonable cost.