I want to replace my Focus ST - what will offer better fuel economy and should I buy a diesel?

I currently drive a 2006 Focus ST which I've owned for four years, and apart from a replacement alternator and door strap the only cost has been routine servicing. The car has now covered 53,000 miles. I love the car but am looking to save money on fuel (average 23mpg) and associated costs and I'm also worried the car is getting to an age where it will start to have issues with the DMF etc.

The problem is, most of my driving is done on short journeys of a few miles and I only cover 12,000 per year, so I don't think a diesel would be suitable due to DPF issues although I understand the Honda Civic diesel doesn't have a DPF. I can save about £1200 per year if I buy a car that will return high 30s mpg plus cheaper insurance etc. The problem is that I would have to put around £4000 into the pot to buy something that appeals (like the Honda Civic) and would end up with a car with more miles than mine, less equipment and obviously far less performance.

Asked on 28 April 2012 by JP, Swindon

Answered by Honest John
I got 45mpg from the Civic 1.8 petrol and from the Citroen DS3 1.6THP 150 petrol. The old Civic 2.2iCTDI up to the end of 2010 did not have a DPF, which is why sales of it had to stop from 1 January 2011. The new Civic 2.2iDTEC diesels do have DPFs.
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