When an engine blows thick white (or bluish-white) smoke, it’s often a sign of internal engine wear. Some Hyundai engines have had problems with major engine components developing premature wear and causing similar problems to the ones you’ve experienced. But some Hyundai engines of this era also suffered problems with the EGR valve (exhaust gas regulation, part of the emissions control system) and that could lead to similar problems.

The best advice is to have the vehicle inspected for internal wear or any other problems that could be causing the smoking under load situation. This is pretty back to basics stuff and would include a compression test and leak-down test and should be well within the capabilities of any decent workshop. From there, you can make a more informed decision on whether to spend the money to have the car fixed, or cut your losses and move on.

It's also worth mentioning that Hyundai has been very pro-active in helping out owners who have experienced premature engine-wear problems, but the age of your car plays against this. It would be worth contacting Hyundai’s customer service division, however.

If you’re lucky, the problem might be as simple as a blown fuse that controls these circuits. So that’s where to start checking. The instrument panel lights and rear fog lights in the Hyundai are on separate circuits, so you’ll need to locate both fuses. Start with the internal fuse box located low down on the dashboard near the steering column. The inside of the cover will have a map of which fuse does what, but don’t forget there’s also a second fuse box under the bonnet.

If the problem is not a blown fuse, or the fuse blows again once you’ve changed it, you’ll probably need to services of an auto electrician to figure out where the power is going and what’s the cause. A poor earth somewhere on the car or a short circuit are two likely culprits.

This was a huge problem for manufacturers back when turbo-diesels first started using Diesel Particulate Filters (DPF). The problems started when owners were using their diesel-powered vehicles just as they had their previous petrol cars. That is, for short, urban journeys where the exhaust system never got hot enough to perform a DPF regeneration (which is critical to the way these filters reduce tailpipe emissions).

To counter that, some manufacturers programmed the engine to dump extra fuel into the exhaust to get it hot enough for a DPF regeneration. Inevitably, however, sometimes some of that extra fuel found its way past the piston rings and into the engine's sump. And suddenly, there was more oil in the sump one day than had been there the previous day.

The problem there was that the diesel now in the sump was actually diluting the engine's lubricating oil, and that could lead to accelerated engine wear and bearing failure. The best solution – then and now – is to make sure you drive the vehicle at freeway speeds for at least an hour every three or four weeks. That will get things hot enough for the DPF to regenerate if it has to, and not rely on the extra diesel the computer will pour into the engine.

You could be looking at a specific DPF problem or maybe a software glitch that is messing up the regeneration, but if the level on the dipstick is rising, then I'd say that's your problem.