Exploring the Pros and Cons of Diesel Cars and Petrol Cars

If you’re in the market for a used car, deciding on the right fuel type can be a crucial step in the buying process. Whilst there is a growing availability of hybrid and electric vehicles, petrol and diesel cars continue to dominate the used car market. So how do you choose between the two? In this comprehensive guide, we’ve included all the information that you’ll need to make an informed decision.

In this article…

What Are The Pros of Petrol Cars?

What are The Cons of Petrol Cars?

What are the Pros of Diesel Cars?

What are the cons of diesel?

Choosing the Perfect Fit: Deciding Between Petrol and Diesel

The 2030 Ban

What are the pros of petrol cars?

Lower running costs: Petrol is cheaper than diesel at the pumps. You’ll typically pay around 2p less at the pump for petrol versus diesel. Whilst this may sound like a minuscule saving, you’ll notice a huge difference over the course of a year.

Less local air pollution

Lower running costs: Petrol is cheaper than diesel at the pumps. You’ll typically pay around 2p less at the pump for petrol versus diesel. Whilst this may sound like a minuscule saving, you’ll notice a huge difference over the course of a year.

Check out this handy guide on how your engine type impacts global warming.

Better for short trips

When it comes to finding a budget-friendly solution for your daily tasks, such as school runs, grocery shopping or navigating through a congested town centre, a petrol car emerges as the best option. With advancements in technology, modern small petrol engines are equipped with turbocharging which offers an ideal combination of responsiveness and fuel efficiency.

Petrol Cars are Typically Quieter:

Whilst there have been advances in diesel engines, petrol-powered cars are still usually smoother and quieter than diesel engines. As mentioned above, diesel and petrol-powered cars work slightly differently, so you’ll hear less noise and feel fewer vibrations with a petrol car, especially when you’ve started it from cold.

What are the cons of petrol cars?

Fuel Economy:

Whilst it’s likely that you’ll pay less for petrol per litre than you would a diesel engine, you could end up using more of it. This is particularly true on longer drives at average speeds, as this is where diesel engines are most efficient.

If you only undertake 200-mile round trips occasionally, the fuel economy may not be a major concern. However, if you frequently embark on long motorway journeys, it’s essential to consider the impact on your fuel expenses. In such cases, opting for a diesel car may be a better option, as they typically offer better fuel efficiency on extended drives.

Higher CO2 Emissions:

Petrol cars emit more carbon dioxide than an equivalent diesel engine. CO2 is one of the primary sources of ‘greenhouse gases’ that are linked to climate change and global warming.

Having higher CO2 emissions may also mean that you’ll have to pay more tax if the car was registered before April 2017. Before this date, the UK Government used CO2 emissions to calculate a car’s annual road tax – the lower your CO2 emissions, the lower your tax fee.

You may also notice that you’re charged more in clean air zones across the UK. It’s always best to check before driving into any major UK city what regulations they have which may affect your vehicle.

What are the pros of diesel cars?

Ideal for Long Journeys and Towing: The Power Advantage of Diesel Engines

When it comes to long journeys, diesel engines have a clear advantage over their petrol counterparts. Their ability to deliver more power at lower engine revs allows diesel cars to effortlessly handle extended motorway trips without straining the engine.

This means they can achieve comparable performance levels while operating at a more relaxed pace. This power advantage also makes diesel cars exceptionally well-suited for tasks such as towing, ensuring a smoother and more capable towing experience.

Enhanced Fuel Efficiency:

When it comes to fuel economy, diesel cars outperform their petrol counterparts. The secret lies in the energy density of the fuel, diesel packs more power per volume than petrol. This advantage translates into significant mileage gains that can make a substantial difference in your driving experience. Diesel engines often achieve an official mpg of around 70mpg, which significantly surpasses an approximate 50mpg for equivalent petrol models.

What are the cons of diesel cars?

They’re More Expensive:

Diesel vehicles typically cost more than their petrol equivalent, mainly because modern diesel vehicles are fitted with advanced technology that reduces their particulate emissions.

They can Cause Poor Air Quality:

The NOx (Nitrogen oxide) gasses that older diesel engines emit are linked to poor air quality, which can lead to breathing problems and other health issues.

Diesel Vehicles Don’t Like Short Journeys:

The majority of modern diesel cars have a feature in their exhaust called a diesel particulate filter that helps to reduce harmful particulate emissions. During shorter and lower-speed journeys, the filter doesn’t function efficiently, so if you do these trips on a regular basis, the DPF can get blocked and cause engine problems – which can be very expensive to fix.

Choosing the perfect fit: deciding between petrol and diesel


The decision on whether petrol or diesel is the right choice for you ultimately depends on your driving patterns and preferences. If you primarily undertake shorter journeys within a town, or urban area, a petrol car becomes the go-to option. Its agility and versatility make it an ideal choice for navigating urban areas efficiently.

Whereas, if you frequently embark on longer journeys, or find yourself clocking motorway miles, a diesel car may prove to be a better fit for you. Its robust power and better fuel efficiency make long-distance travel a breeze.

The 20230 ban

It’s worth bearing in mind that the government plans to phase out the sale of new petrol and diesel vehicles by 2023 to promote the adoption of lower-emission cars such as hybrid and electric vehicles. This won’t necessarily impact the used car market though, which has a plethora of choices for both petrol and diesel models.

So, whether you prioritise city manoeuvrability or long-haul efficiency, assessing your driving habits and considering future developments can guide you towards making an informed choice that aligns perfectly with your needs and aspirations.

Are you in the market for a used car?

Don’t let the process of financing your dream car be a hassle. With Marsh Finance, you can apply for finance in just 30 seconds, and you’ll find out if you’re pre-approved on the same day.

Representative Example

Rates from 12.9%

Representative example: borrowing £10,000 over 60 Months with a representative of 23.0% APR, an annual interest rate of 23.0% (fixed) and a deposit of £0.00, the amount payable would be 59 repayments of £269.58 per month, with one final repayment of £279.58 (which includes the option to purchase fee of £10.00), with a total cost of credit of £6,184.80 and a total amount payable of £16,184.80. Marsh Finance Limited are a lender, not a broker. 

Marsh Finance Limited are a lender, not a broker.

This is for illustrative purposes only and is not a quote or an offer of finance.