Diesel or Petrol

Diesel or Petrol Engines?

Are you thinking about purchasing a new car, if you are then it is important you make the right decision about which type of fuel suits your motoring needs.  Diesel engines have clearly advanced over the last decade making them more appealing to non business users and this has meant a huge increase in their market share.  Petrol engines are fighting back though with more efficient smaller engines, here are a few key points about each fuel which might help you make the right decision.

Diesel Engine Pro's

  1. Diesel engined vehicles tend you have a higher resale value then the petrol equivalent.
  2. Diesel engines can save you money on fuel if you make regular long journeys.
  3. Diesel engines have more torque than the petrol equivalent meaning fewer gear changes  and lots of overtaking flexibility.
  4. Lower vehicle excise duty due to the greater fuel economy.


Diesel Engine Con's

  1. Diesel engine vehicles are more expensive than the equivelent petrol model. 
  2. Occasionally servicing can be more costly than petrol engines.
  3. Parts tend to be more expensive for diesel engines.
  4. The cost of diesel at the pump is higher then petrol (higher fuel tax on diesel).
  5. Diesel vehicles tend to emit more particulates than petrol.
  6. Diesels are generally more noisy (in a bad way) so not what you want if you are buying a sports car.


Petrol Engine Pro's

  1. Cheaper to buy than the diesel equivalent.
  2. Quieter than a diesel engine.
  3. Sometimes cheaper to service with less frequent service interals.
  4. Cheaper parts.
  5. Petrol vehicles are cheaper to fill up at the pump.


Diesel Engine Con's

  1. Reduced fuel economy on longer journeys.
  2. Lower resale values.
  3. Bigger cars with petrol engines have to be driven harder to make overtaking manoeuvres,  so using more fuel.


How has the engine technology changed?

Diesel engines used to be noisy and dirty. However a number of advances in technology have meant a dramatic improvement in their efficiency and performance making them more appealing to us all.  Diesel engines do not use spark plugs like a petrol engine, instead they use a glow plug.  The glow plug helps to keep the surrounding area in the engine block warm enough to aid the combustion of the fuel on cold mornings, this is why with older diesel engines you had to wait a few moments before fully turning the ignition key, now though it takes a split second to do this.  Sound insulation has also improved reducing the noise into the cars cabin and around the engine bay, this means that it is sometimes hard to tell what type of fuel the car is running on.

Petrol vehicles have also advanced.  Smaller and more efficient petrol engines are now available which can easily match the performance and provide greater fuel economy then much larger petrol equivalents.  This has been achieved by the use of smaller turbo chargers which help to deliver the punch needed to overtake or simply put a smile on your face on that quieter stretch of road.

Summary of Diesel and Petrol Engines

Whether or not you should purchase a diesel or petrol engined vehicle is a difficult question to answer.  There are so many pros and cons for both and myriad of claims by manufacturers, but which should you buy?  I don't think it is possible to simply decide based on facts and numbers, the way a car drives, sounds and makes you feel has to be a factor taken into consideration.  If you are a company car owner running up and down the motorway then diesel is an obvious choice, if you make short journeys in and out of your local town then petrol would be a more sensible option.

A number of return on investment calculators can be found online which can help you decide if the extra investment in a diesel vehicle is valid for your needs.  Depending on the number miles you cover it can take a few years to start saving yourself money if you purchase a diesel vehicle so think carefully about the choice you have to make!