Which one is better petrol or diesel?

If you compare apples to apples the diesel really only offers better fuel economy. You can't compare a normally aspirated gas engine to a turbo diesel. A fair comparison would be to compare a turbo gas engine to a turbo diesel engine, once you do that, the torque advantage that the diesel may have isn't as drastic. With a diesel you have more limited operating range in terms of engine speed, you pay for the diesel up front, you pay more to service the diesel, and you pay more to fix the diesel (though they do tend to be reliable). What you get; better fuel economy, and often a longer service life. I supposed if you live in a country with oppressive fuel taxes then it could make sense though. But I wouldn't have one.

diesel if more fuel efficient and your mpg (miles per gallon) will be a lot better than an equivalent size petrol engine. diesel is more expensive per litre but only by a few pence which im sure will still work out cheaper than petrol. diesel engines used to be louder to but now they are the same as any car. diesel does burn slower than petrol though so if you are looking for something quick, its likely the best engine would be petrol. overall. also the better mpg it gives you the lower the tax group giving you another saving, personally diesel is better.

if you use over 15000 miles a year diesel is better less than that petrol that is on cost or if you intend to keep the car a long time diesel again

Diesel should be banned, filthy, smelly even more unhealthy than petrol.

Neither is better. Each has advantages and disadvantages.

mix them in a cocktail and drink them. then you'll find out. but you'll probably die from poisoning

The real clincher is whether you do a large mileage. Diesel engined cars are generally more expensive to buy and to service, but offer better fuel economy and often cheaper road tax. The power and torque (and at what revs they are delivered) varies a lot between petrol and diesel cars, so they will feel different to drive. Which is "better" is a matter of personal taste. Diesel engines are generally better for carrying heavy loads or for towing. One concern about modern diesel engines is the cost of repairs - a new set of injectors, fuel pump or turbo can easily cost more than £1000. Petrol engines, by comparison are simpler, so less expensive to repair if they go wrong.

If you are doing 15000 miles per year, with a fair amount of motorway then Diesel every time. If you are running it as a local shopping trolley then petrol. Modern diesels are kitted out with special exhaust systems to protect the environment from soot, and unless you do a regular burn-up they are so much trouble. Also the higher cost of diesel, and the higher cost of the vehicle needs an awful lot of miles to break even. I'm currently running diesel and while the drive is good, the costs not so good

mainly a personal choice these days. petrol's are easy to service, have good rev range and are fairly quite and trouble free in main. life of the engine will depend on regular service and not being thrashed. a diesel costs more on servicing and parts but tend to be renowned for longevity when serviced regularly. buying new isn't cost effective due to additional costs of this engine form new. ideally a three year old one is best and then run until it is six. after this things need replacing such as particulate filters etc and gets very expensive. noise isn't normally a problem these days except at idle. biggest difference is rev range with diesels running out of oomph very quickly and needing more and quicker gear changes. resale values will depend on car but for example a ford fiesta diesel versus petrol values will drop faster on petrol over 6 years than diesels. bottom line wil be to be clear what you are using it for? pulling a lot of weight or towing,hill climbing and long motor way journeys a Diesel is overall better. for round town and short trips petrol beats all.