There’s not a lot of good news here for the home mechanic, I’m afraid. No doubt some of the code-readers you can buy online will do the job, but it’s all a bit of a lottery. In many cases, you’re buying a code-reader from overseas, and while it might cover the car you own, it might be loaded with the software for a different version of the same model. Also, you can’t update the reader with new software as it becomes available and, in many cases, you’ll need more than one code-reader to cover all of the car’s systems.

According to a lot of workshops, generic code-readers aren’t worth the bother and will often only give you the fault code-number, rather than an explanation of what the fault actually is. Sometimes, they’ll just flash up a message that you should refer the problem to a dealership. Not very helpful.

I spoke to a Daewoo specialist workshop about this and was told that the code-readers worth bothering with start at about $8000 and go all the way to $12,000. Which, I imagine, is more than you wanted to spend.

Is it using oil? Does it blow smoke from the exhaust? If the answer to those questions is no, then I would be looking for an oil leak from the engine.

CONTEMPORARY road tests gave the average fuel consumption of the Kalos at 7.5 litres/100km so yours does seem particularly high. First, make sure everything is in order with the engine and emission system. Take it to a mechanic who knows his stuff. Hopefully the dealer is reputable, not simply trying to get rid of you by telling you all is well. Something in the emission system could have failed and is telling the engine's computer to run rich.