Looking back over the year and seeing how the diesel engine has changed we thought we would dust off our crystal ball and try to look into the future.

Since the humble beginnings of the diesel engine, which was designed to run on peanut oil, the diesel engine has evolved into quite an extraordinary beast

Way back in the 1930's / 1940's the diesel engine found it's niche market where a power plant was required to be heavy duty, had low down torque, used less fuel than gasoline and had it's optimum power/torque range relatively low in rpm range, this market was in agriculture (tractors), locomotive, marine, heavy trucks, high output generators and military vehicles such as tanks.

Gasoline engines were, in comparison, less robust, heavy on fuel and provided maximum torque/power quite high in the rpm range.

Diesel engines where always known to be noisier than gasoline, had less power than gasoline (for same cc of engine) gave more smoke than gasoline but these downsides were always outweighed by the diesels 'positives'.

Diesels were never even considered an option for cars and vans (for mass production) until the late 1980's / early 1990's when manufacturers developed engines with just enough power and engines that were not quite as noisy, lets not forget that the price of diesel fuel back then was massively less than petrol!! So the option of running a diesel car/van became very attractive.

During the 1990's the diesel market truly kicked off with the legendary Peugeot / Citroen XUD lump setting the pace, the mid 90's saw the VW 1.9 TDI arrive which truly put the diesel car as a superior option to petrol.

By the end of the 1990's we had pretty much all car manufacturers offering a diesel powered vehicle in all classes of car (small to luxury). To nicely 'tie in' with this diesel car boom the price of diesel fuel cost more than petrol! Funny how years earlier diesel cost less and still odd and unexplained is the fact that diesel fuel is less refined than petrol so actually costs less to manufacture!

Hovering around car production is the ever present 'face of doom' in the form of environmental bodies who have to justify there existence by whatever means necessary.

Suddenly car manufacturers were set stringent exhaust emission figures so vehicles had to be built that produced emissions no higher than what was stated, vehicles producing higher emission figures could not be sold, these 'limits' where termed 'Euro' ratings (e.g. Euro 3, Euro 4) for road going vehicles and 'Tier' ratings (e.g. Tier 1, Tier 2) for industrial / agricultural vehicles.

Exhaust emissions had been previously set back in the early 1990's, but hey, if it aint broke, change it anyway!

To meet these exhaust emission figures we saw the arrival of the EGR (Exhaust Gas Recirculation) system in the late 1990's which reduced emissions at idle speed and light throttle.

In the early 2000's the hippy influence really kicked off and EGR systems alone could not meet the more stringent emissions so more intensive emission reduction methods where introduced.

To highlight how the diesel engine has evolved and in which areas, we have compiled a sectioned 'slice' of diesel history.

Diesel engines up to the early 1990's

POWER - OK, not spectacular.

NOISE - POOR, 'diesel clatter' and vibration very noticeable.

EMISSIONS - POOR, smoke on start up usually heavy, heavy smoke under load very common.

ECONOMY - OK-ish, smaller diesels quite efficient, heavy diesels very poor.

RELIABILITY - EXCELLENT, bullet proof, built to last and they did.

Diesel engines from the early 1990's to early 2000's (noughties)

POWER - VERY GOOD, loads of torque and power.

NOISE - GOOD, certainly acceptable, vibration virtually extinct.

EMISSIONS - VERY GOOD, smoke on start up virtually eliminated, smoke under extreme load only.

ECONOMY - EXCELLENT, figures for some cars reaching late 50's mpg to early 60's mpg.

RELIABILITY - VERY GOOD (on the whole), car/4x4/van engines reaching 200k+ miles easily.

Diesel engines from the early Noughties to current

POWER - EXCELLENT, high end marque cars breaching 200bhp with ease.

NOISE - EXCELLENT, only slightly more noise than a petrol.

EMISSIONS - EXCELLENT, very slight smoke under very heavy load.

ECONOMY - EXCELLENT, cars often reaching 50-60mpg.

RELIABILITY - POOR, sensor faults aplenty, major engine faults seen in less than 100k miles.

The main reason for the dramatic improvement in terms of power increases, lower emissions and reduced noise levels was due to the introduction of 'common rail' injection systems.

Perhaps one phenomenon is the coincidence of harsher emission standards and the 'talk' of global warming nicely being introduced around uncertainties of world oil supplies, around the very late 1990's. The emission requirements effectively meant that common rail injection was the only option for engine builders to use to meet the stringent emissions figures.

Diesel engines COULD have taken a VERY different route.

The emphasis could have been to build engines that could safely and reliably use 100% vegetable oil based fuels that had no reliance on fossil fuels at all. The effectively 'forced' use of common rail systems massively hindered the step to vegetable based fuels as common rail injection is awfully weak and sensitive to fuel composition. Further additions of particulate filters in the exhaust caused further issues for running on vegetable based fuels as the by products from the burning of veg based fuels blocks exhaust filters very quickly.

The 'leaps' towards cleaner, more environmentally friendly diesel engine technology virtually rendered the modern engine to be fossil fuel only.

Conspiracy theory lovers may see a clear correlation between oil producers and car manufacturers with a little help from politicians to ensure demand for fossil based diesel is kept at the maximum.

Should diesels of taken the vegetable based fuel route massive areas of land would of been required to grow the necessary crops, this would of meant reliance on (and giving a degree of power to) countries with a large land mass such as Africa and Asia, something that would be very unlikely to happen any time soon.

So as things stand at the moment with meddling from hippies, politicians and outrageous fuel prices the future for the diesel engine does look quite bleak.

More and more emission reducing components will be added, more complicated and sensitive injection systems will be developed in an attempt to increase economy and reduce exhaust particles. This will result in less reliable vehicles, shorter life engines and bigger repair bills.

A sorry tale for what was the 'ultimate' engine. a demonstration of how a few hippies and politicians can change a perfect design into an unreliable headache.

Reading this one may think we are 'anti-diesel', this is not the case. What we have serious concerns about is the constant bombardment of legislation the diesel engine is being hammered with and the very spurious reasons why the legislation is imposed in the first place, man made hysteria that is effectively killing the diesel engine.

In saying that, Diesel Bob Tuning (UK) Ltd will be here to assist with all your diesel fuel system issues and keep costs down where possible.

Hybrid, electric and hydro vehicles may be the hippies choice of transport but it's certainly not ours!!