While the most fuel efficient BMW 3 series 1983 E30 sedan diesel - BMW 324d for 100 kilometers consumes 6.9 liters of diesel. According to user reviews, BMW 3 series real-world fuel consumption is on average about approximately for 6 percents higher as the manufacturer's claimed fuel economy (on average +10% for petrol engines and the same for Join Date: Mar 2006. Location: Bristol England. iTrader: ( 0) I also have a 320i and that fuel consumption is way too high. I had to do some quick conversions but based on a total of 13,000km, my car has returned an average of 9.9 litres per 100KM, a best of 8.3 litres and a worst of 10.9 litres per 100km. Fuel Consumption - Economy - Combined: 28 MPG 8.3 L/100 km 34 MPG UK: Fuel Consumption - Economy - Open road: 37 MPG 6.4 L/100 km 44 MPG UK: Fuel Consumption - Economy - Highway: 31 MPG 7.7 L/100 km 37 MPG UK: Fuel Consumption - Economy - City: 22 MPG 10.9 L/100 km 26 MPG UK: Range : 487 miles / 783 km: Fuel Tank Capacity : 17.2 gallons 65 L 14 Fuel consumption: at 90 km/h l/100 km: 7.1: at 120 km/h l/100 km: 9.1: Urban l/100 km: 13.9: BMW ALPINA C1 2,5. Based on BMW: 325i (E30) 2-, 4-door, All-Wheel 101. The E30 collection: 1987 325es M52 - Schwarz / Taurus Red Sport (son #2's) 1987 325is - Delphin / Black Sport (son #3's) 1987 325i Convertible - Triple Black. 1989 325iX Coupe - Diamondschwarz / Black Comfort. 1990 325iX Coupe - Sterling Silver / Grey Sport. 1981 Fiat 124 Spider 2000 - Green / Tan. BMW 3 Series Cabriolet 1985, 1986; What is the body type, BMW 3 Series Convertible (E30)? Cabriolet, 2 Doors, 4 Seats: What is the fuel economy, BMW 3 Series Convertible (E30) 325i (170 Hp)? 9 l/100 km 26.13 US mpg 31.39 UK mpg 11.11 km/l: How fast is the car, 1985 3 Series Convertible (E30) 325i (170 Hp)? 216 km/h | 134.22 mph 0-100 km/h: 8.7 sec 19–59. Real MPG. 40.1. Average. Superb to drive. Great handling and steering. Upmarket image. Economical diesel engines culminating in amazingly efficient 320d Efficient Dynamics at 109g/km of CO2. cm5MxU.