Gasoline vs diesel? A never-ending question and dilemma.
In the remote past this question was easy to answer. If you wanted a performance car, gasoline was the name of the game.
On the other hand if you wanted a rugged servant, good for work and load, diesel was the answer.
But near the end of the 20th century something happened: major car manufacturers saw great potential in the diesel engine and began to develop it to once unbelievable heights and performances.
That development made the question even harder to answer. Simply, the past clear line between gasoline and diesel engines started to get bleak and dim.
Making a proper choice when buying a new or used car regarding the engine type has become quite a task and demands some good thought and reasoning.
Hopefully this article will give you some guidelines and help you solve this dilemma.
First, some basic differences will be mentioned between these two engines. Afterward, you’ll see some of the main factors which you should consider when making this decision.
MAIN DIFFERENCES BETWEEN A GASOLINE AND DIESEL ENGINE
I won’t go much into the technical differences of these two engine types as this is a topic on its own for sure.
We’ll just mention a couple of most obvious technical differences as well as a few other important ones from a drivers point of view.
If you want more technical details, click on the two lower links for a great in-depth explanation on Wikipedia.
TYPE OF FUEL THAT’S USED
This is the main and most obvious difference.
There is a great difference between these fuels two in terms of refining, ignition point, etc.
Won’t go into much detail here, perhaps the most important part for a driver is not to mix them up when putting fuel into the tank.
Driving performance is one more difference that you’ll certainly notice.
In previous times, when the diesel engine wasn’t so advanced, the difference was noticed right from the start. The gasoline engine was sharp, easily revved up and there was no hesitation once you pressed the accelerator pedal.
Diesels, on the other hand were sluggish, slow-responsive to the gas pedal, and needed ages to gain speed. Very limiting factor when, for instance you wanted to make an overtaking.
In newer times, that difference is all but gone. Diesels have become a major powerhouse with tones of torque at a moments disposal and a very equal rival to their gasoline counterparts.
In the past, there was no mistake on this one. Gasoline engines had a subtle, smooth, purring sound while the diesel engine hammered away with its unpleasant clanking.
Nowadays, the difference is almost gone. Diesels have been ˝silenced¨ thanks to modern technologies regarding fuel injection systems, muffler systems etc.
I say almost as the difference can still be noticed if you listen more carefully. The gasoline engine has maintained its smoothness and borderlines total lack of sound while the diesel engine has a nice sharp growling tone to it.
Fuel consumption is perhaps the main reason why drivers have a gasoline vs diesel dilemma.
Diesels were always known for their dramatically lower consumption than the gasoline engines but paid for it through poor performance.
Gasoline engines had better performance but were in most cases gas guzzlers, especially if you had a lead foot on the accelerator pedal.
Modern technology made diesels better in terms of performance but still kept the fuel consumption at very affordable limits, even bordering unbelievable.
Gasoline engines have also evolution-ed a lot. Gas guzzlers are the thing of the past and you can get a very decent performance for a reasonable amount of spent gasoline.
More on fuel consumption lower in the article.
DASHBOARD WARNING LIGHT
The most noticeable sign of recognition if you’re not into cars.
Once you turn the ignition key on a diesel car, the well known curled wire sign will appear for a short moment before starting the engine. This will happen on modern diesel engines only if the engine is cold.
For gasoline engines, in most cases, there is no such type of warning sign.
More about dashboard warning lights in a separate article which you can see by clicking here.
Gasoline engines have a lower compression rate while diesel engines have a higher one.
IGNITION OF AIR-FUEL MIXTURE
Gasoline engines ignite the mixture with a spark plug while diesel engines use a glow plug to previously heat up the cylinder (when the engine is cold) and then use compression to ignite the air-fuel mixture.
Diesel engines have a reputation for lasting longer than gasoline engines. On average this is, mainly, true.
Diesel engines can also take more punishment in terms of towing and driving under harsh conditions (which is one of the main reasons they’re installed in trucks and pick-ups).
I wouldn’t want to comment much on this part as there are many factors that influence the longevity of the engine that are not related to the engine type.
Some of them are proper maintenance, driving style, quality of build, etc.
I will just say that every engine can last a long time and be durable if you use it the right way and properly maintain it.
GASOLINE VS DIESEL-WHICH ENGINE IS BETTER FOR YOU?
If you want to make a good decision you have to take into account these important factors:
1. MILEAGE OR KILOMETER STAND OVER THE YEAR
This factor is one of the most important, if not the most important, in the gasoline vs diesel question.
If you’re going to make a lot of miles or kilometers over the year (more than 20,000 kilometers) then the diesel option is definitely for you.
Less fuel consumption is the main reason why people choose a diesel engine for frequent long-distance travel. Many kilometers with less fuel means a lot of saved money.
If the mileage is lower (especially under 10,000 kilometers a year), better go for the gasoline engine. Low mileage probably also means short distances and in this case a smaller gasoline engine is good. Also, cheaper to maintain.
So, lots of miles or kilometers means you should buy a diesel. Less kilometers, go for gasoline.
2. FUEL ECONOMY
Diesel engines have always been known for low fuel consumption and have been a champion over gasoline engines. Even with the high tech modern technologies, the gasoline engines still take second place.
For instance a 1,9-liter diesel engine with common rail and 115-120 bhp will take on average 6,5 liters of diesel every 100 kilometers. This is an average for combined driving.
If you take the same car with a gasoline engine (like 1.8 or 2.0 liter) and the same amount of horsepower it’s bound to take at least 1 liter of fuel more (truth be told, it’s more like 2 liters) per every 100 kilometers.
Case closed on this part.
3. FUEL PRICES
You probably already know all of the fuel prices in your country. When talking about the gasoline vs diesel question, this is a major factor.
Try to make a choice that will be friendly to your budget. Whatever fuel is cheaper, buy a car with that type of engine.
If everything is OK, you’ll be owning that car for years to come so driving on cheaper fuel will save some serious money.
4. BUDGET FOR BUYING A CAR
When planning a budget have in mind that new diesel cars, on average, are more expensive than gasoline ones (about twenty percent).
At least this is the case in my country and from what I’ve seen in most of Europe (perhaps worldwide).
For instance an average middle-class car with a gasoline engine will cost about 20,000 Euros. The same model with similar specs but with a diesel engine will cost about 22,000 to 23,000 Euros.
With used cars, the situation mainly depends on the car market and the popularity of the engine type. On average, cars with diesel engines are more expensive to buy but hold their ground much better over time.
5. MAINTENANCE COSTS
Modern diesel engines are gems of technology, no doubt about it.
But that didn’t come without a cost.
You see, in order to enhance the diesel engine to crank out a lot of torque, get rid of the sluggish response, and still maintain a low level of fuel consumption, car manufacturers had to do various things.
New systems of fuel injection (common rail for instance), adding a turbo compressor, intercooler, injectors for very high pressures are just some of the novelties present on all of today’s diesel cars.
More high tech parts mean more complications and more complications mean a higher maintenance price.
Modern diesel engines have a high cost of maintenance compared to gasoline engines. You have to be prepared for various expensive repairs, some are in the regular maintenance interval and some are not.
The mentioned injectors, service of the turbo compressor, EGR valves and the infamous dual mass flywheel is something that certainly awaits you, especially when buying a used car with a diesel engine.
If you want to read about the symptoms and cost of a dual-mass flywheel replacement click here.
Gasoline engines, on the other hand, have their fair share of problems too. But, if nothing else, they are, in most cases, cheaper to fix and less complicated.
For instance a lot of cars with gasoline engines don’t have the dual-mass flywheel.
6. PRIMARY PURPOSE OF THE CAR
What will be the main purpose of the car? Travel, commuting to work, hauling a trailer, car for work, or a hobby perhaps?
These are some of the questions you have to ask yourself when solving the gasoline vs diesel dilemma.
If your going to use the car for some sort of work (like as a delivery vehicle), travel long distance frequently (like if your job is far away), have passengers all the time or make a lot of miles or kilometers altogether, then a car with a diesel engine is certainly the right choice for you.
Small distances, less mileage, lots of driving by yourself, or less usage of the car altogether will mean that a gasoline-powered car is a better choice. The best one in this case is with a smaller engine (up to 1.5 liters).
As mentioned, the gasoline vs diesel dilemma used to be easy to solve when it came to performance.
If you wanted performance and didn’t care how often you visit the gas station, gasoline was for you. If you wanted something reliable, save some serious gas money, and don’t care the least about performance then you definitely chose diesel.
Since then, the situation has changed drastically. Today’s diesel engines are loaded with torque (power) and in a lot of cases overcome, by far, their gasoline counterparts.
In short, what was once the exclusive realm of the gasoline engine has now been overtaken by the diesel.
Simply, when you press the accelerator pedal on a modern diesel, in most cases, it puts a smile on your face. They go like the wind, have no problem producing enormous amounts of torque in seconds, and at the same time maintain a good level of fuel efficiency.
Gasoline engines, on the other hand are also good but always need that revving up in order to maintain a constant level of performance. High revs mean higher fuel consumption and if you’re a fan of revving up all the time it’s a question of how long will the engine last.
On the part of the performance, I would always recommend a modern diesel engine. Huge amounts of torque, instantaneous power, comfortable driving, low fuel consumption….can a driver ask for more?
If it wasn’t for the expensive maintenance for the diesel engine, I would say it was near perfect.
Ecology is an important factor nowadays for car manufacturers and especially for ones that make diesel engines.
Diesel engines were known to be the mother of polluting when it came to exhaust fumes. But with today’s technologies of filtering the particles, efficient combustion, enhanced catalytic converters, and else, polluting is brought down to the bare minimum.
Gasoline engines had and still have fewer problems with this (even with older type engines). Catalytic converters solved those problems efficiently even at the beginning of the ecological awareness period.
In the gasoline vs diesel equation (regarding ecology) one more factor goes in favor of the gasoline engine.
These engines have the possibility of converting into LPG (liquid propane gas). They successfully use LPG instead of normal gasoline which is both ecologically and budget-friendly.
So, if your really ecologically aware, buy a car with a gasoline engine and convert it to LPG. Better than a diesel engine by far regarding ecology. Mother Nature will suffer the least with this option.
To tell you the obvious truth, the ultimate solution to this part is to buy an electric car.
Next best thing is a car with a smaller gasoline engine converted to using LPG.
In some ecologically aware countries you may even get extra benefits for using this fuel.
Talking about ecology, in almost all modern countries there are taxes for exhaust emissions.
Diesel engines are a definite loser on this part despite the fact that modern technologies have reduced emissions to a bare minimum.
Thanks to legislative and policies, there is a present trend of banning the diesel engine altogether.
A result of that is higher eco-taxes and certain restrictions (like you can’t go to certain parts of the city if you drive a diesel, for instance the downtown center).
On the other hand, cars with gasoline engines have a much better position.
Less emission means less taxes and present gasoline models meet future eco-standards more successfully.
Besides ecology, the tax factor is relevant for future re-sale or if you plan to keep the car for a prolonged period of time.
Less emission means fewer taxes so you’ll be able to save some serious money for sure.
10. TRAVEL AUTONOMY
Diesel engines are the king of the road here. Low fuel consumption combined with a bigger gas tank will give you some very serious travel autonomy.
Even cars with smaller diesel engines and gas tanks can travel about 700 kilometers on one tank.
On bigger cars with bigger engines that have 50, 60, or even 70-liter gas tanks, driving over 1000 to 1500 kilometers on one gas tank is normal.
On this part, the gasoline vs diesel dilemma goes in favor of the diesel.
Simply gasoline engines have higher fuel consumption on average and the only remedy would be installing a bigger gas tank which is not an option for the same car model.
11. POSSIBILITY OF RESALE OVERTIME
Big factor in the gasoline vs diesel question. The choice on this part highly depends on the car market, brand, and engine type popularity in your country.
Buying a new car with an engine type that is more popular means a higher resale price, faster sale, and lower depreciation in the future. (if you want to read more on how to slow down car depreciation, click here).
The used car market is more or less the same. Cars with the more popular engine are more expensive to buy initially but hold a better resale price.
After all of these factors and recommendations comes the last but perhaps most useful one:
Buy what you NEED!!!
You don’t need a 3.0-liter diesel torque monster to go to the grocery store two days a week.
Opposed to that, you certainly don’t need a 1,2-liter gasoline ¨vacuum cleaner˝under the hood for frequent long-distance travel.
Of course, there is also the matter of what you prefer. Some people wouldn’t drive either a diesel or gasoline car if it would save the world.
But I think this preference should be secondary if you want to make a quality choice.
Just know that every one of these engines has its pros and cons. Neither of them is flawless.
What I can recommend, in both cases, for mid-class everyday exploitation:
Diesel engines (and this is a highly subjective opinion) are best in the range between 1.5 and 2.0 liters. These engines offer a very decent amount of torque, can drive successfully a mid or upper-sized car body (or a van), have a good amount of horsepower, and keep the fuel consumption between 6 and 8 liters per every 100 kilometers.
Simply these engines are a great all-rounder for everything. The downside is the expensive maintenance.
In the gasoline engine realm, I would go for engines up to 2.0 liters max. I would recommend the 1,6 liter as this engine has a good fuel consumption to performance ratio.
So a 1.6 to 2.0-liter gasoline engine as a middle-class all-rounder. Fuel consumption here is within normal boundaries (on most cars), averaging about 8-9 liters for every 100 kilometers.
In the end, the gasoline vs diesel dilemma will be present as long as cars are powered by these engines.
Deciding has always been tough and the never-ending improvement of both engines will make it even harder in the future.
The only thing that can put a certain end to this dilemma is the electric car, that’s for sure.
Written by: Sibin Spasojevic
Former car technician, life-long car and DIY enthusiast, author for Despairrepair.com