'NEW car launches come and go very quickly and are soon forgotten. Like buses, another will always come along fairly soon.

But every now and then a car hits the showrooms that creates more than usual awareness and car buyers don't just want one – they want it now! For a limited time they make 'over list' and as the hype builds, everyone wants to get in the act.

That includes the speculators who see a way of making a fast buck. But very few cars can maintain this level of excitement and the waiting lists quickly fall from years to months. This is partly driven by those who place orders through multiple dealers, then cancel all the rest once the first manages to deliver.

This leaves manufacturers in a delicate position. They would love to say their car is so fabulous there is a four-year wait, but they know that the list will soon be reducing and they could even end up with a shortage of orders if publicised waiting times put people off.

So, immediately after the launch manufacturers have to sift through orders to weed out the multiples.

There are some cars that do genuinely have a long lead time, but regular mass-produced cars are a different story. The only advice that can be given is – if you really want a certain car then order it once and be patient because it will probably arrive sooner than expected.

DEALERS are worried about the growing evidence that supermini diesels are not proving as popular as first thought. Some of them have a list price premium of about £1,000 over the petrol equivalent but the public is just not prepared to pay it. You have to do big mileage in a 'baby diesel' to get your money back, and who wants to do that in a small car?'