TDI Explained

TDI is an engine technology developed by Audi, first presented in 1989. The first car released with this technology was a diesel engine with turbo charging, direct injection and electronic management at the Frankfurt Motor Show(IAA). From this platform turbodiesel technology with direct injection boosted to major success.

TDI of course, stands for Turbocharged Direct Injection. This features turbocharging and cylinder direct fuel injection. Direct Injection involves a fuel injector spraying atomised fuel directly into the main cobusion chamber of each cyliner. (wheras indirect injection where the atomised fuel is sprayed into the pre-combustion chamber).

The engine also uses whats known as forced induction that increses the amount of air that is able to enter the engine cylinders. On top of all this most TDI engines use an intercooler which lowers the temperature of the 'charged' or compressed air from the turbo, allowing a larger abount of fuel to be injected and combusted.

If youve ever driven an Audi with a TDI engine you can feel the difference in the engine with regards to power. You can get lots of torque from low revs. You can feel the great performance and power. On top of this they have great economy. This is what makes the TDI variant the most popular (albeit expensive) choice in any Audi range.

There you have it, TDI