Modem passenger cars have to meet very strict targets for emissions and fuel consumption in an effort to reduce their contribution to atmospheric pollution and the generation of green house gases. Diesel engine vehicles produce considerably less carbon dioxide (the main green house gas) than petrol vehicles because they are more efficient but theydo produce more pollutants especially particulate matter, which is known to have health implications for humans.To achieve future emissions and fuel consumption targets such that the Diesel can be classified as 'clean', a range of low polluting technologies are being developed. These technologies can be very expensive and complex to control, they also interact with each other and sometimes the combination may not have the overall potential that was first envisaged. Such findings may not become evident until a long and costly testing programme has been undertaken. Consequently, there is little consensus as to the best combination of new technologies that will result in a commercially viable clean diesel car. The process still requires many years of research, on-engine testing and vehicle trials to ensure the chosen combination provides the desired effect.This project aims to use computer models to simulate the performance of modern Diesel engines and the vehicle in which they are fitted. We plan to use these models such that will 'interact' and 'talk' with one another with some degree of intelligence such that they can identify the likely technology winners without the need for a lot of time consuming test work. This constitutes a virtual environment for assessing complete system performance, this is a highly attractive possibility but a substantial research effort is required to prove that it has merit.Inevitably, some experimental testing will be required to evaluate how well the models predict performance in a real world environment. Because we are dealing with technology that has still to be refined, or even developed, we will need to use experimental techniques that recreate boundary conditions (manifold states, temperatures etc) which will appear to the engine indistinguishable from those generated by the proposed technologies. By using this approach we will be able to identify the best combination of technologies and demonstrate their potential to reduce pollutants and improve engine efficiency. Additionally, we will need to ensure that the car can still be driven with the same expectations as current products. To this end we will predict subjective vehicle performance when equipped with the proposed technologies.We will be working with a major car company and as the project progresses they will assist us in the acquisition of the technologies we have identified such that they may be fitted onto an engine in a vehicle. We will predict the performance using the modelling tools we have developed and finally we will test the complete vehicle and assess how well it performs and how accurate our predictions have been. This will be the crucial test of the usefulness and robustness of the techniques developed.We plan to demonstrate simulation techniques that can identify and predict where diesel engine improvements can be made by adopting certain technology before it becomes available. If we are successful this will benefit our environment by bringing clean diesel engine cars to garage forecourts much quicker and will also reduce the development costs of the manufacturers.