Are diesel cars still cheaper to run than petrol?

I’ve driven diesels for the past 10 years.
I believe it’s the best choice for me, as I do around 25,000 miles a year.

It’s the not economy so much that keeps me with diesels (I don’t think there’s an awful lot in it between petrol and diesel where that’s concerned nowadays), it’s more to do with the robustness of the engine and its potential long life compared to a petrol engine.

I’ve actually never had a diesel engine break down on me, the problem I find is with the rest of the car. Usually the engine will outlast the running gear, (suspension, steering and so on). These seem to be areas of cars which are not built to last. Nowadays things like brake discs are designed to wear out in parallel with brake pads, ridiculous. Bulbs are often impossible to change by yourself, also ridiculous.

Cars are deliberately designed in such a way that the home mechanic can no longer maintain them. It’s all a big scam to rip off the motorist that has no choice becuase he/she needs a car.

Sorry, going off topic now, but I could rant for hours on this….

Diesels here for a long time, mostly all over the south of England but sometimes further. Had a chance to try a Nissan Leaf a while back and loved it. I think that’s the future. I did about 70 miles in it in various urban stages and it only cost a couple of quid (charged overnight in the garage). I wouldnt take it on the motorway, yet.

The manufacturers will continue to charge a premium for diesel engines because diesel is still much cheaper than petrol in most European countries. Although car prices vary between European countries, diesel remains the cheaper fuel in general, so UK diesel car prices are unlikely to converge with the UK petrol car prices.

You have to look at how many miles you do. With some of the comments here, diesel is absolutely the right choice for them as they do lots of miles every year.

I recently bought a new car and decided that diesel was not for me with as I drive under 10,000 miles per year. You also have to consider how long you will have the car. I have never owned a car longer than 2 years and I certainly won’t be keeping my current car any longer than that because it’s a new Mini and built as well as a 1970’s Rover.

I chose petrol due to the responsiveness of the engine and the price compared to diesel relating to my usage. Plus if you choose a small car (low weight) then you can save money that way too.

You have to add a turbo to get any performance though, my girlfriends car when up for renewal will probably have the VAG 1.4 TFSI engine with a super and turbo charger where you get performance and economy.

I belive that with automatic cars there is a completely different story. I have a Mitzubishi Colt (2008) automatic one and I am happy with its consumption. (around 55-60 mpg). Not sure if there is an automatic petrol care that would have the same consumption.

Surely not just £ costs should be considered but also the comparative CO2 emissions of the two types of engine, also the emission of micro-particles by diesel engines (especially below 2.5 micrograms size), which I understand are strongly implicated in lung diseases and mortality. Regarding these particles, I understand that particulate filters can trap these, but that (as stated in a box item linked to the Which? article), these filters get blocked if cars are just used for short urban journeys.

When buying a new car ten years ago I worked out that the difference between cost of the car and the cost of diesel, it would take me 7 years to break even if I purchased the diesel and I did a fairly high mileage in those days. Diesel was so much cheaper in those days too. I am surprised it has taken Which so long to do such a comparison.

I’ve been driving diesels for 3 decades, plus motorbikes and now a Mazda MX5 petrol car. I prefer diesels as does my wife, for the solidity and driveability. I must admit I’m in a quandary over our next purchase. Our old 406 Peugeot HDi estate has done 175k miles and we plan to replace it with a Ford Kuga Titianium. A 1 year old diesel was a no-brainer but I’m having second thoughts. We’ll do less than 10k per year, the particulate filter could cost a fortune to replace and the 2.5 petrol model is a lot cheaper (and rarer). I doubt the cost of the latter’s depreciation will be so different to compensate buying a diesel. Times they are a changing

I guess if you run an artic, a taxi, or you never go anywhere without your caravan, you’d probably want to go for diesel. For any other purpose I can’t think why you would. The downsides of diesel include the awful smell, the bizarre power delivery characteristics of a turbo-diesel that make it so easy to accidentally spin the wheels at 5 mph but runs out of puff at 3,000 rpm, just when you really need to complete that overtaking manoeuvre, and above all else the noise like a bag of spanners in a tumble drier. So many articles point out that diesels are so much quieter now, and can barely be detected in the cabin, and to an extent that’s true, but the noise outside continues to be alarming. I saw (and heard) a lovely new Jaguar XF which clearly had a big diesel under the bonnet taking off at a very fast lick from the M6 tollbooths. Looked lovely but we had the window open to pay the toll, and this beautiful car sounded like a Transit van on steroids. Even my wife looked at me and asked “What was wrong with that car?”

I run an A6 with a 3.2 litre petrol and after 146,000 miles it’s still luxurious and with a creamy power delivery that builds smoothly all the way to the red line, and still gets 32 to 36 mpg. My wife has a new Scirocco with the marvellous 1.4 TFSI engine with turbo and supercharges. It’s incredibly nippy, but very frugal, although probably wouldn’t be good at towing a caravan!

My previous car, which I had for 17 years was a diesel and I never had any trouble with the engine. I would still be using it, but due to a shoulder injury I needed power steering so had to reluctantly change.
My new car I bought in 2009 and is also diesel. It has a very small tax charge, and perhaps because I don’t need to use it in the town for shopping, it is very comparitively cheap to run. I live in a small market town , so use it mostly to travel between 10 to 60 mile journeys to the surrounding local places which of course have no public transport and the car is the only way to get to them. With the exception of a couple of extensive journeys a year, my fuel bill is about £50 every two months.so I find diesel a good choice rspecially as the engines seem very reliable and long lasting.

There is no clear answer to this question, it depends on several variable factors. Buy a new car, keep it only three years and do modest mileage and you’ll find the diesel models higher purchase cost means no savings will be there.
However many of us buy used cars. The purchase price difference is nothing like as big and especially if you do average or above average annual mileage the diesel will work out cheaper. Add to this that diesels engines tend to last longer than petrol and you’ll find that secondhand diesel is a good buy.
Diesels have come on a lot in recent years and are much less like the “tractors” they use to be but still many prefer the smoother petrol engine. If you want diesel economy and the smoothness of petrol try an LPG car. I have one and would have another, 71p per litre but admittedly lower MPG. Still works out at under 10p per mile fuel cost and, if you run out of gas it will still run on petrol.
I’d say that compares well, but you of course have to buy a car already modified to run on LPG, a £1500 to £2000 retrofit leaves you with the same comparison problem.

These calculations really only work if you only ever drive in the UK. We drive all around Europe and diesel is consistently cheaper than petrol. It would have been useful to point this out in the article. It was a major factor in our choice of a diesel estate.

For the high mileage drivers diesel seems to be the clear winner – provided you don’t think anything matters except money. Unfortunately there are no clean diesels yet – the existing cleaner diesels still emit lots of invisible particulates that petrol engines don’t, and many still emit NOX pollutants that cause illness too. These invisible particulates turn up in inside our tissues – even getting into the brain. As a result of health concerns, there are tighter emission standards on the way for diesels that are likely to increase their initial cost and reduce mileage as filters and reduced compression ratios come in. The present ones are likely to be allowed to carry on killing until they wear out, unfortunately. In case you think this extreme, bear in mind that air pollution in London, most of it from diesel, kills about twice as many people each year as road accidents in the whole of the UK. They just die out of sight. Especially in cities, electric cars, buses and taxis can’t come fast enough. It’s much better to clean up our power stations than to try to clean up each vehicle.

My experience is based on E Class Mercedes cars which which give far greater benefit for the Diesel model than your article would suggest. Not surprisingly, Mercedes sell more than twice as many Diesel than Petrol cars of the same model. Instead of new Diesel cars being dearer, they are in fact cheaper to buy. The cost of fuel may be 3% higher, but the fuel consumption of the same size engine is 30% less for the Diesel car. Instead of taking many years years to recoup the higher cost of the Diesel car, the benefit is immediate, even for low milage use.

One obvious flaw in this analysis is not to consider the residual value of the respective cars. It would be interesting to see how these compare.

Several people have commented that diesel in Europe is cheaper that in Britain, one garage in Germany last month was selling diesel for 1.40 Euros and petrol for 1.56 Euros per litre, this might be an exception, but all garages I passed in Germany, Belgium, France and Spain petrol was considerably dearer.. If these differances were repeated in the UK then surely there would be no contest between petrol and diesel cars. When I first bought a diesel 8 years ago diesel was cheaper. What changed to make it dearer than petrol other than the fuel companies greed?

In my limited experience modern diesel engines are less reliable than petrol. However, I suspect it depends upon the type of use they get. Traditionally diesel engines were considered better than petrol for short journeys. Since the development of low lag turbo engines I think this may no longer be the case.

Six years ago I bought a new Skoda Octavia with the 2 litre TDi engine. With under 50,000 miles on the clock I started to get a problem whereby the engine would suddenly lose power, often at an inconvenient, sometimes dangerous, moment when you need the power. Without displaying any warning light the engine management system would go into a ‘get home’ mode and disable the turbo boost. Stopping the engine and restarting would reset the engine management system and normal power would be restored. This gradually became more frequent to the point where it would happen on most journeys.

I was told that the turbo was probably at fault due to carbon deposits preventing the variable vanes from adjusting freely. Apparently carbon can build up if journeys are short and/or are at low speed.
A Skoda franchise garage estimated a replacement turbo would cost in the order of £1,200 fitted. Fortunately I managed to have the turbo reconditioned through a non-franchise garage for a fraction of that and it’s rectified the problem. The garage told me that a reconditioned turbo should last as long as a new turbo. They said that they recondition a lot of these turbos for the local taxi companies and that the problem isn’t confined to the Volkwagen Audi Group – it’s a general problem with the variable vane technology which is designed to reduce the lag associated with traditional turbos. I understand that carbon build up is not a problem with these type of turbos in petrol engines.

Since then I have had to have a new throttle body because the butterfly valve system failed.

My two cars prior to this diesel were petrol – one was a 6 cylinder, the other a 4 cylinder turbo. I had both from new and kept them to over 100,000 miles. Apart from both requiring new batteries (as you might expect), the engines were faultless.

If you do a lot of long distance driving then diesel may be for you. I don’t. My next car will be petrol!

In my opinion I think diesel engines last a lot longer than petrol engines, I had a 2002 diesel Mondeo which had 127,000 miles on the clock but showed no sign of wearing out or loosing power, I reckon its new owner will be able to get another 127,000 out of it.
Question: It has been reported that diesels will be obsolete in 5 years time, is this true?