Car Clinic: Oil thirsty Audi A2, left-hand Porsche 911 dilemma, rogue emissions warning light and "camber-conscious" Vito

The Car Clinic experts

THE DEALER
Jason Dawe is our used-car expert and has appeared on Top Gear and the Morning Show

TIM’LL FIX IT
Tim Shallcross used to train AA patrols to fix cars. Now he advises the Institute of Advanced Motorists.

Q. In the 10 years I have owned my Audi A2 it has needed to be topped up with oil every 2,000 miles or so. My husband’s BMW has never required oil between services. My Audi dealer says this happens with some A2s and it’s just “luck of the draw”. Can you provide a better explanation?

RMJ, Oddington, Gloucestershire

Oil consumption is affected by factors including engine design, driving style and journey length. Anything up to one litre every 1,000 miles is considered acceptable in modern engines, which tend to rev harder, have higher compression and run hotter than those of a couple of decades ago. All those things make them use more oil.

The A2 petrol engine is known for high consumption but it is still within reasonable limits. In fact Audi made a slight change to the engine in 2004 — the piston oil control rings were modified — which reduced its thirst for oil a little. The reason the BMW uses less is probably down to driving style and the fact that the Audi is likely to have a higher-revving engine, which can burn oil more quickly.

TS

Q. I aim to move back to Britain from Kuwait and would like to bring my 3½-year-old, left-hand-drive Porsche 911 Carrera S with me. If I do, will Porsche UK service it? And would I be able to sell it in Britain?

TB, Kuwait City

The car can be serviced by any authorised UK Porsche dealer. To ensure it is compliant with UK law, your Porsche will be subject to “individual vehicle approval” when it arrives, which involves checks and adjustments such as ensuring that the headlights and fog lights are correctly aligned, that its emissions are legal and that the speedometer is calibrated in mph (the switch can be made electronically on your Porsche). Once it passes the test, the car can get an MoT certificate and registration document.

Companies that specialise in shipping and approval testing include mycarimport.co.uk (which quoted about £4,500 for shipping, testing and registration of the vehicle) and shipmycar.co.uk. The process will take 8-12 weeks.

UK prices for left-hand-drive Porsches will be lower than for right-hand-drive ones, but there is a market. Sales are fairly rare so it’s difficult to be accurate about prices, but your 911 is worth about £5,000 less than an equivalent right-hand-drive model. This gives a price of £32,000 in a private sale (assuming it’s a 2010 car with average mileage and a manual gearbox) or £27,500 in part exchange.

JD

Q. My 10-year-old Volkswagen Polo failed its MoT test after the exhaust emissions warning lamp came on. My garage fitted a new oxygen sensor and the car then passed — but the warning lamp remains lit. My garage can’t solve the problem. Any ideas?

PL, Leeds

The light is on because the engine management computer has detected a faulty reading from one or more sensors in the fuel management and exhaust system. As your car has passed its MoT, it is likely that a sensor or its wiring is faulty. One possible diagnosis is a problem with the second oxygen sensor: the Polo has two, one each side of the catalytic converter.

The first sensor makes sure the air-to-fuel ratio is correct (vital for the catalytic converter to work properly in reducing exhaust emissions). The second is there to ensure the first one and the catalytic converter are doing their jobs properly. If the latter sensor isn’t working properly and is giving peculiar readings, the warning light will come on; but if the first sensor and the catalytic converter are working properly, the emissions will be fine, which is why the car passed the MoT.

The car’s computer will have stored this information — that is, which sensor detected the peculiar reading — in the form of a fault code. Most garages will have a reader that can be plugged into the car’s computer to download the code. Insist that your garage does this and carries out a proper diagnosis before you authorise further work.

TS

Q. As soon as I bought my new Mercedes-Benz Vito van, I noticed that the steering pulled to the left — even on straight, even roads. The mechanic says he has corrected the tracking and the rear tyres, which were overinflated, but the problem persists. My dealer claims all Vitos are “camber-conscious”. Have you heard this expression?

DM, Burton upon Trent, Staffordshire

You are not the only Vito owner with this complaint. “Camber-conscious” and “they all do that” appear to be typical dealer responses. The fact is that the Vito is not designed to pull to the left when being driven in a straight line; its suspension is sensitive to being slightly out of adjustment, and fixing it can be time-consuming.

Vehicle suspension is complex and there are several angles (principally camber, caster and wheel alignment, also known as tracking) that need to be set correctly to give stable handling, even tyre wear and accurate steering. On the Vito, alignment (the slight angle the wheels are pointing towards or away from one another) and camber (the angle of the wheel to the vertical) are adjustable on the front axle and should be checked.

The camber angle varies according to suspension height, so it should be checked in several positions. It may be possible for a mechanic to vary the camber angle of the nearside wheel to compensate for the van’s left-leaning tendency while staying within the tolerances allowed by the manufacturer.

The fact that the alignment was out and the rear tyres were overinflated when you took delivery of your van suggests that pre-delivery checks were not done thoroughly. We advise you to return to your dealer and insist the fault is corrected.

TS

Got a car problem?

Email your question to carclinic@sunday-times.co.uk, or write to Car Clinic, Driving, The Sunday Times, 3 Thomas More Square, London E98 1ST, with a daytime phone number, your address and as much detail about your car as possible. We can’t reply personally, so please don’t send original documents or SAEs. Advice is offered without legal responsibility.