This extremely efficient combustion process pays dividends in a number of key areas. Apart from improving fuel consumption, emissions and power, it is crucial in helping to iron out the strong vibrations traditionally associated with compression ignition.
Low levels of NVH (noise, vibration and harshness) inside the car are due to the engine's advanced combustion technology as much as its careful chassis installation. This includes the adoption of an electro/hydraulic power steering system, for improved fuel consumption, and additional tuning of the front suspension and wheel angles.
The high level of driving satisfaction is reflected in the standard fitment of a close-ratio, six gear manual gearbox that encourages driver involvement, complementing the sporty nature of the 1.9 TiD engine and the Convertible's chassis, with its unique ReAxs rear wheel steer characteristic.
The optional six-speed Aisin AW automatic transmission is a smooth and adaptive unit, responsive to changes in engine load, road gradient or altitude, and quickly finds the ‘right’ gear without any irritating ‘hunting’. The driver can also switch to manual control by using a sequential floor shift or optional steering wheel-mounted buttons. It features a lock-up in all forward ratios, except first.
Advanced Particulate Filter
The 1.9 TiD powertrain includes the most advanced diesel particulate filter on the market. Unlike other particulate traps, it is maintenance-free and self-cleaning, requiring no additives or periodic replacement.
Located in the exhaust system downstream of the close-coupled catalyst, the housing for the filter also includes a secondary oxidation catalyst to remove residual hydrocarbons (HC). The exhaust gases pass through this first, before entering the filter's ceramic core, made from a honeycomb of silicon carbide. This is perforated along its length by a matrix of microscopic channels, which collect the particulates as deposits from the exhaust.
In order to clean the filter and keep the exhaust gas flow as free as possible, these deposits are periodically burnt off by short pulses of over-fuelling. These briefly raise exhaust temperatures to the required level of 600º C. The process is automatically initiated when back pressure in the exhaust system reaches a certain level and it is completely undetectable by the driver.
This innovative solution has been made possible through the fuelling flexibility provided by the engine's multiple injection strategy. The self-cleaning process takes place whenever necessary, irrespective of throttle load or engine temperature.
British deliveries of the new Saab 9-3 Convertible 1.9 TiD models commence in late February, with on-the-road prices ranging from a competitive £25,370 for the Linear model, to £27,664 for the sporting Vector derivative. The special metallic blue 20th anniversary Cerulean edition is also temporarily available in Vector form at £28,439.
The UK market for four seater premium diesel convertibles is expanding rapidly, and Saab’s new entry into this sector is certain to ensure continued growth. Saab forecasts the new 1.9 TiD will account for at least 20 per cent of all 9-3 Convertible sales in 2006.Published 12 January 2006