Michael McAleer answers your queries
From P O'D, Dublin:
I've got a 1998 BMW 3-series and a friend has introduced me to a firm in Britain which will change the electronic control unit and give me 250bhp. That's a serious power increase, but what exactly are the risks?
The first thing to note is that you are required to inform your insurance company. Despite the fact that conservative estimates put the number of Irish cars chipped each year at 500, less than 2 per cent of these inform insurance companies of the changes. They run a serious risk if they get involved in an accident.
For others there's the risk of invalidating the warranty, but in your case this doesn't apply. For you the big issue is the increased chance of mechanical problems, such as engine overheating and turbo damage. Some independent garages advertise power increases up to 1,000 bhp, but it's accepted that output should not be boosted by more than 30 per cent.
Cars can be tuned up because car makers, believing customers are not going to look after their cars, set up ECU units to under-use engine capabilities and extend component life. But, for people who maintain their vehicles correctly there is no need for such a safety margin.
Our advice is to stick by the 30 per cent rule and get the car thoroughly looked over by someone else so they can work out if the parts are up to the tune-up. Otherwise the thrill of extra power may be shortlived.
From G Meehan, Cork:
I'm in the market for a used family car, with around €12,000 to spend. I'm trying to decide between a Toyota Avensis and a Nissan Primera, both 2001. Any advice or suggestions?
Tough call - both should serve you well over the years. But check service histories, mileage and state of interior.
In the end it might come down to personal choice, in which case I'd probably opt for the Avensis if it was between the two. But either one should serve you well if it meets the usual criteria for buying used.
From William Aylmer:
As the approach roads to the capital revert to car park mode in the first weeks of the new school year, I wonder what car drivers must be thinking as I pass them by at much the same places each day.
My journey is a 12 mile spin each way along the N 81 approach, enough to test the most patient car driver but no doubt far from being the most challenging commute for the average Irish motorist.
It takes me about 30 minutes each way on the motorbike, no matter when I leave, the only limitation being speed limits and traffic lights. The same journey in a car takes over an hour each way.
On a rough calculation, that means my car driving colleagues (my wife being one) spend the equivalent of at least a full working day in traffic for every two working weeks.
Have they ever considered leaving the car at home and buying a motorbike? I started six years ago when I was 32 after 14 years of driving a car.
There are other advantages too - I can get home fast if the baby gets sick, I can leave work mid-week at 6.15pm and make that training session by 7pm (most of my team mates will have left the office before 5pm and that's if they make it at all), annual road tax is €67, petrol is €20 a week. My two brothers envy the time I save and my niece thinks its "bling".
I wonder too if Messrs Brennan and McCreevy ever seriously considered incentivising changeover from car to bike. It strikes me as an obvious way to help reduce city congestion.
Employers too can surely find ways to help their employees make the change. If it works in major Asian cities, why can't it work for us?
The biggest problem for motorbikes remains its poor image in relation to safety. This in turn is largely due to the lack of training many bikers have before setting out.
As one of those car-driving commuters, stuck in traffic for hours on end, the idea of weaving through the gridlock sounds very tempting. But the thought of being soaked all winter and fried in leather all summer is also a deterrent. You might not be moving in an air-conditioned car, but you're comfortable. It's also a little oasis of personal calm in the hectic regime of modern life.
From David Blackmore, New Zealand:
I may just have the answer to John Doherty's problem (Helpdesk, June 16th). [John Doherty is getting married in January and, as a complete "classic Mercedes nut", hoped for a Mercedes 600 Pullman limo as the wedding car. - Ed.]
We have a choice of not one, but three Mercedes 600 Pullmans and a very rare 600 Landaulet. Two of the Pullmans are matching six-door versions originally owned by Hugh Hefner (if only they could talk) and the Landaulet was last owned by a Colombian gentleman whose importing business has earned him 15-to-20 in a US penitentiary. The cars can be seen at www.number1.co.nz
Of course, John may have to rearrange his wedding plans to include a trip to lovely Auckland, New Zealand. If he does, the car hire is on the house.
Send your queries to: Motors Help Desk, The Irish Times, Fleet Street, Dublin 2 - or e-mail them to motorshelp@irish-times.ie