Car clinic: How will proposed smoking ban in cars affect driver with teenage passengers, and why does my Jaguar XF S 3.0D hesitate?

The car clinic experts


Tim Shallcross used to train AA patrols to fix cars. Now he advises the Institute of Advanced Motorists.


Dominic Tobin is a motoring journalist who has campaigned successfully on consumer issues.


Q. I have read about the proposed smoking ban in cars. How would it affect a smoker with two teenage children aged 16 and 17? Given that both teenagers are legally able to smoke, would the ban still apply if they were passengers?

KB, north London

A. There are still several stages for the proposed legislation to pass through before it becomes law, and it is by no means certain that it will be passed. If it is, it is likely that adults will not be able to smoke when any teenage children are in the car, even if the children are old enough to smoke. Draft legislation to enable a ban on smoking in cars that carry children was added to the Children and Families Bill last week. It must now pass a vote in the House of Commons. The government indicated that MPs would be given a free vote, which many commentators believe makes it more likely the bill will go through.

Even if the bill is passed, the ban will not automatically come into effect. The legislation only allows the health minister to create a law “making it an offence for any person who drives a private vehicle to fail to prevent smoking in the vehicle when a child or children are present”.

It is not yet clear how the law would operate, apart from establishing the principle that the driver must ensure that nobody in the car smokes if a child is present.

However, some clues were provided by another amendment to the bill, which was not voted on. It was backed by campaigners including the British Lung Foundation (BLF), which is likely to be consulted if the ban is brought into law. The amendment suggested that the new law should apply when anyone in a car is under 18 — the minimum legal age for buying cigarettes — and that drivers found guilty of the offence should have to pay a £60 fine or attend a smoke-free-driving awareness course.

The BLF estimates 430,000 children a week travel in cars while an occupant is smoking but says it expects drivers to stop in the event of a ban — just as the majority clunk-clicked their seatbelts when it became illegal not to.



Q. Sometimes when I am trying to accelerate quickly in my 2011 Jaguar XF S 3.0D automatic there seems to be a lag before the engine picks up. This can be disconcerting, especially if there is oncoming traffic. Any idea what is causing this?

AG, Carterton, Oxfordshire

A. Your car has an eight-speed automatic gearbox made by ZF, a German manufacturer. Our diagnosis will differ depending on whether the problem occurs when you are accelerating from a standstill or from a low speed. If the car is moving slowly, the gearbox will probably be in second gear. When you put your foot down hard, the gearbox computer realises you want maximum acceleration and changes to first gear. This takes only a fraction of a second but can be noticeable if your are expecting to surge forward immediately.

You can eliminate the lag if you select Dynamic mode, using the button by the gear selector control, or Sport mode on the selector itself. Either will raise the gearchange speeds so that, just as in a manual car, you remain in a lower gear for longer when accelerating hard. The gearbox will also move down the gears at higher speeds as the car slows, switching down to first gear at perhaps 7-8mph instead of about 2mph in normal driving mode. This means that when you slow to approach a roundabout, say, and then want to accelerate again, the gearbox will already be in first gear. Your fuel consumption will suffer, though, so you might want to change back to normal mode once you have completed your manoeuvre.

If selecting Sport/Dynamic mode doesn’t cure the lag, or if the problem occurs when trying to accelerate from rest, ask your dealer to check the transmission computer. As with most modern automatic gearboxes, its computer is designed to learn and adapt to your usual style of driving, gearchange patterns and other information. This means the system can develop software glitches. Clearing its memory might resolve the problem.




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