Petrol cars are generally less fuel-efficient than diesels
You might pay less for petrol per litre than diesel, but you could well end up using more of it. That’s particularly true on longer drives at higher average speeds, where diesel engines are at their most efficient.
It probably won’t register if your only long car journey is the annual 200-mile round trip to see relatives but if long motorway journeys are a regular feature in your life you’ll probably spend a lot more on fuel with a petrol car.
Higher CO2 emissions
Petrol cars emit more carbon dioxide (CO2) from their exhaust pipes than an equivalent diesel and CO2 is one of the primary ‘greenhouse gases’ linked to climate change.
That higher CO2 output also means you’re likely to pay more in tax with petrol cars registered before April 2017. Before that date the government used CO2 emissions to calculate a car’s annual road fund licence (more commonly called ‘road tax’). This means that cars with lower CO2 outputs – usually diesels and hybrids – costs less in tax.