TTT and anyone else, if you are interested most modern car / small van diesels are TDI , which stands for Turbocharged Direct Injection. This has only been possible since a fully computerized fuel injection system was developed , previous engines ( and some current diesel engines) were/are CRDI which stands for Common Rail Direct Injection.
The differences are explained here
http://www.differencebetween.net/business/product-services/differences-between-crdi-and-tdi/
Basically TDI means a far more 'petrol like' performance , quieter and much less 'diesel Knock' which is what I assume TTT is talking about . TTT you need to make sure the car you try is a TDI diesel as both my Zafira and mikeys cars are. You really do not know it's a diesel unless you look at the name badge , apart from the far superior fuel economy of course!
Another difference is that a CRDI engine needs a separate fuel pump which keeps the entire fuel system from pump to cylinders at very high pressure. These fuel pumps are very reliable but do need specialist maintenance. In a CDI the entire fuel pump / injection system is computer controlled and adapts to the circumstances such as air / engine temperature and humidity. There is no maintenance, if it goes wrong you just put in a new computer chip.