6 Tips for Improving Your Cars Diesel Engine Efficiency

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Although most people drive vehicles with gas engines, the diesel engine has been making advances in recent years. A diesel engine is more efficient than a gasoline engine. With fuel prices so high, making your diesel engine even more efficient can help save you even more money.


Biodiesel fuel has been touted as a very green alternative to diesel. It’s true that there’s plenty to recommend it as it drastically reduces emissions and cuts your carbon footprint. You can also make your own biodiesel if you wish.

These are all excellent advantages but biodiesel won’t give the same kind of mileage as regular diesel. Both performance and miles per gallon, which are big efficiency factors, can be 10 percent lower with biodiesel when compared to normal diesel in a diesel engine.


Drag can have a detrimental effect on fuel efficiency in a diesel engine. One of the biggest causes of drag is driving with your windows rolled down when going in excess of 35 miles per hour.

This creates much more resistance, especially if you have more than one window down. You’ll cut your fuel bill if you only have a window slightly rolled down that's enough to create a small breeze in the vehicle.

Air Conditioning

Driving with your air conditioning on will means that your diesel engine will run less efficiently, as more of the power is taken to power the A/C and keep the air cool. You’ll be much more efficient if you just run the fan on cool, instead.

Tire Pressure

All vehicles will run better if they have the proper tire pressure. You should use a tire gauge to check the pressure and compare against the pressures recommended in the owner’s manual.

This will give you more miles per gallon with your diesel engine. It’s important that you check the pressure regularly, and also make sure your tires aren’t worn to maintain the optimum diesel engine efficiency.

Driving Habits

One of the greatest factors affecting the efficiency of a diesel engine, or any engine, is how you drive. By developing good driving habits you can greatly increase your engine efficiency and mileage per gallon.

You should avoid sudden acceleration or braking. Both these things eat fuel. The more smoothly you drive, the less diesel you’ll use. Similarly, driving fast might get you somewhere faster, but you’ll pay for it with a less efficient engine. Find the cruising speed that uses the least fuel and don’t go faster than that.


You can put additives into your fuel to increase the efficiency of your diesel engine. This is quite commonly done, especially with poor quality diesel fuel. Adding kerosene, for instance, can improve the miles per gallon you get. You’ll also find it makes your fuel greener by reducing emissions.

Other types of additive are designed to increase the efficiency of your diesel engine. The problem with most of these is that you need to add them to every tank of fuel, which increases the cost of your diesel. Before buying additives, research first to be sure they actually work.