Some unexplained diesel smoke mysteries

I am far from being an expert on car engines, so there are things to which a total ignoramus like myself cannot attach a logical explanation.

Firstly, even in the so-called Third World (to which we so stoutly profess not to belong) I have never seen so many diesel-engined vehicles puffing out black smoke.

The popular explanation is, I believe, dirty injectors.

Do all our diesel-engined car owners neglect to clean their injectors, while all their counterparts in other countries do?

The funny thing is that even new cars seem to do it. When I put this conundrum to my trusty car mechanic, he explained that it's not always due to dirty injectors. Boy racers tweak their engines to improve performance, he declared, and the resulting enriched mixture does not burn completely.

Now, knowing the large numbers of wannabee Schumachers on our roads, this sounds plausible. Except for one thing! Large, opulent-looking executive cars, driven by dignified, white-haired gentlemen and very obviously quite new, are unlikely candidates for either category, so that puts this one out.

And the buses!

This is probably an exaggeration, but it seems to me that here every bus spouts thick black fug. It is said that the price of kerosene has been hiked to stop bus owners lacing their diesel oil with it to improve running costs.

But, then, why do buses still smoke? Is there some other medium besides the now-too-pricey kerosene with which to "improve" diesel fuel?

Unworthy thought: And could it be that bus drivers are being held exempt from prosecution on this count? (remember the famous police go-easy-on-hunters memo debacle)

Anyway, continued my knowledgeable car mechanic, whatever the reason, this situation is not going to prevail for long. In future ADT will be sealing diesel engines so that they can't be tampered with. If this is true, is it actually happening?

Another thing. It was announced some time ago that diesel fuel quality was about to improve (so the quality was bad!) Did it, actually? The black smoke is still with us.

So why do vehicles still smoke?

The facility to SMS-report smoky vehicles is still in operation, but does not appear to be effective.

Many suspect that the whole rigmarole is merely an elaborate bit of eyewash to cover up the fact that authorities are powerless - or disinclined - to do anything about it; either because sub-standard fuel is the culprit, or because it would be a vote-loser. (In my humble opinion, showing clearly that you are not controlling a given situation is more of a vote-loser, but that's another matter, let's not go out of subject.)

Is this operation actually producing tangible results?

Also, I wonder if police constables and wardens consider that the existence of this 5061 1899 facility exempts them from the obligation to report offenders?

The public deserves an answer to these questions. Or do we wait till the EU slaps another fine on us?