Diesel vs Gas Car Which One Is Better

So, you’re looking to buy a new car? You’re probably pondering whether a diesel or petrol car would be better for you. It’s not a new question, but it is a common one. Regarding petrol vs. diesel vehicles, fuel is not the only differentiating factor, so we have put together this guide to help you make a more informed decision. 

NOTE: Come and talk with our car experts if you are in the market to buy a new car. Our specialists at the Cambridge premium used car dealership can help.

Fuel Efficiency 

Generally, petrol cars are less fuel-efficient than their diesel counterparts. Depending on the car you purchase, as well as the engine itself, a diesel engine will typically burn 15-20% less fuel than a petrol engine, meaning you can go further on less fuel. However, this efficiency comes at a cost. 

A diesel engine needs to be made with heavier materials that have been designed to withstand the higher compression ratios necessary for the combustion process to take place. Petrol engines, on the other hand, have a lower compression ratio and can, therefore, be made with lighter materials that cost less – lowering the cost of a petrol car. Diesel engines also require more maintenance than petrol engines, which is an important consideration to keep in mind. 


Staying on the subject of maintenance and servicing, the cost of servicing and maintaining your car as a whole should also be considered before you select the preferred fuel option. Petrol engines operate on spark plugs, whereas diesel engines will focus only on compression to ignite the fuel, so the forces that are generated on the engine components are much higher.

Consequently, the components in diesel engines will need to be stronger and are, therefore, more expensive to make. The complexity of diesel engine mechanics makes servicing and repairs more expensive.

Additionally, the cost of spare parts can be quite steep. Overall, the cost of maintenance and servicing for a petrol engine will be much lower, but a diesel engine will likely last longer. 

Diesel engines typically last longer than petrol engines because of the property of the fuel. Diesel is a light volatile fuel that also lubricates the engine parts as it burns inside the engine, resulting in reduced wear and tear. 


The debate about diesel vs. gasoline emissions is still ongoing. However, modern emissions standards and regulations have led to both new petrol and diesel cars being relatively similar in terms of emissions. 

Although older diesel engines can be quite polluting, modern diesel cars can be as clean as petrol equivalents thanks to AdBlue or diesel particulate filters (DPFs) that trap soot from exhaust gases.

Recent research by an international team representing six countries has shown that diesel cars can emit less polluting gases than gasoline cars. The study was published by the journal Scientific Reports. The research showed that diesel fuel is cleaner than ever thanks to better filtration systems for reducing pollution. 

The Price of Petrol Cars vs. Diesel Cars

Petrol cars are usually cheaper than diesel cars and are often more reliable. However, diesel models have the upper hand in fuel economy and low fuel costs, even though their maintenance and repair costs are higher. 

Petrol cars are also more powerful than diesel cars because of the higher RPM and initial acceleration. However, the torque produced by a diesel engine gives diesel cars better pulling power. 

It’s important not to decide based on the car’s fuel efficiency alone. Consider the estimated running cost of the car and the length of ownership before you buy it. A diesel car is best if you plan to keep the vehicle for a long period of time and have a driving distance of around 80-100 km per day. A petrol car is probably better if you are not planning to drive the vehicle for more than three or four years.

Special Interest Automobiles Cambridge prioritizes giving the best automotive services money can buy. Located in Cambridge, Ontario, we sell used vehicles for any type of budget and specialize in a wide range of automotive repair and maintenance.

Contact us today to find out how we can help you.