Road Test: Renault Megane Expression. 1.9 Dci

With its focus on safety, comfort and economy, Renault’s turbo-diesel Megane 1.9 dCi makes a lot of sense.

By: Cameron McGavin. The Age.

• Diesel engine is gutsy and economical
• Quiet and comfortable ride
• Competent handling
• Classy and comfy cabin
• Loads of toys and safety gear

• Bad

• Auto gets weaker engine
• Not the sharpest-driving small sedan
• Steering lacks feel

Little diesels.

Lightweight cars with exceptional fuel economy from their small diesel engines

By: Julian Edgar, AutoSpeed.

World’s Smallest Diesel

The DaimlerChrysler Smart FourTwo features the world’s smallest direct injection diesel engine. The 800c turbo 3-cylinder develops 33kW at just 3800 rpm.

Over the European fuel test cycle, the FourTwo diesel engine gives fuel economy of 3.3 litres/100km and emits just 88 grams of CO2 per kilometre.

Fuel injection pressure is 1600 Bar and 7-hole injectors are used. A large amount of exhaust gas is recirculated – as much as 60 per cent of exhaust gases are cooled and then returned to the combustion chambers.

As is the case with other current direct injection engines, the electronically-controlled diesel uses a pilot injection squirt that ignites and preheats the cylinder, reducing noise emissions.

A tiny turbo is fitted. The compressor has a diameter of only 33mm but it rotates at up to 280,000 rpm. A maximum boost pressure of 1.2 Bar is used. The small turbo and diesel configuration allows for low-rpm torque development – 85Nm is available at just 1500 rpm!

However, the 770kg car is abysmally slow – 100 km/h comes up in a fraction under 20 seconds and top speed is only 135 km/h.