Hi Geraldine,

It entirely depends on the type of driving you do and how far you travel on most journeys. The diesel Mokka is much more economical on fuel (and hence tax), but if it's not being used at higher speeds for decent lengths of time then it's likely that its DPF (diesel particulate filter) and other components will get clogged up, necessitating potentially expensive fixes. Put simply, if you drive short journeys only, or all at low speed, a petrol Mokka is likely to work out cheaper in the long run, regardless of motor tax or fuel economy.