Last week I bought a 07 Sxi VVT 1.6 5 door petrol vehicle, having part exchanged a X reg (Nov 2000) 1.8 Renault Laguna for it. However, the petrol consumption for the Astra seems to be lower under urban conditions, despite the car being much newer and with a smaller engine.

During the week whilst driving to work (around 10 miles each way) I am generally in fairly heavy traffic, with a lot of traffic lights to negotiate and a lot of stopping and starting. Under the same conditions I could get around 31-32 mpg on average from the Laguna but in the week that I've owned the Astra I'm only getting around 28-29 mpg.

What is the optimum mpg for my sort of driving conditions ? Does anyone achieve significantly better results from the same car ?

Look forward to hearing from you.