Expert answer

Hi Anna,

Sounds like either the coolant temperature sender unit or an issue with the air flow meter. These items may not be picked up by the diagnostics. In many cars you can just disconnect the air flow meter to test if it's working properly. Try that first. The coolant temperature sensor will be relatively cheap to replace.

Let us know how you get on.

Expert answer

Hi Pierce,

Overall it's proving to be a reliable car with no major mechanical issues. There are a few things to watch out for on used examples, including uneven front tyre wear - indicating that the alignment is out. Scan the dashboard for warning lights too, as the particulate filters clog if the car isn't used at higher speed very often - and there are isolated reports of issues with the electronic parking brake.

Finally, ensure all the seat belts are in good order - including the adjusters - and that the electric windows all work as you'd expect them to.

Hope that helps

Expert answer

Hi Eoin,

We contacted Volkswagen in relation to your question and 'officially' there does not seem to be a simple solution.

Thankfully there is the unofficial way of doing things and this is something we have experience with having swapped the sports seats in a Mk IV Golf for Recaros from the GTI. A quick search of a certain well-known online auction site reveals that Alcantara sports seats are available, but the shipping costs can prove prohibitive - unless you live near the seller of course.

Our advice would be to contact a large car dismantlers like http://www.traynors.co.uk/ or http://www.eddietorrensinternational.com and see if they have the parts you require. The actual fitting of the seats is just a case of undoing a few bolts and clips with the only problem you might encounter being the possibility of the airbag wiring loom not matching up. This is a simple fix for any auto electrician though and should not cost much to rectify.

We hope this helps.

Expert answer

Hi Justin,

It's not surprising to hear that the car won't go off-road - few do!

In terms of safety, the 2005 Volvo trumps the Discovery with a better Euro NCAP crash test rating.

The Volvo has a marginally better reliability record too, though most Discovery problems (affecting electrics and software) seem to apply to individual cars. Saying that it's worth ensuring its air suspension is in perfect working order. On the XC90 the injectors can play up, and they're expensive to repair, so get suspicious if the car doesn't start quickly.

Evidence points to the Volvo having the lower running costs too, with slightly better fuel economy and of course lower annual road tax due to the smaller engine. Maintenance will be costly enough in both cases, as could be insurance.

In cold hard facts it looks like the Volvo wins this battle Justin, but we'd not be put off the Discovery so easily - it's a great all-rounder as well.

Let us know how you get on.

Expert answer

Hi Brian,

Congrats on number two! Overall the S-MAX is a great family car. It's good to drive, and the 2.0-litre 140 engine is the pick of the range, being economical and powerful. Sounds like the car you've been offered is well specified too. Seeing as you have 'only' two kids it's unlikely you'll need the third row of seats, which is good, as using them results in a tiny boot. They fold flat into the floor though leaving plenty of space for travel systems and change bags.

In general the S-MAX is pretty reliable, though get its chassis number checked with a dealer, as it has been the subject of a few recalls - just to make sure all the necessary work has already been carried out. Other than that, make sure every single switch works as it should - especially with such a high specification.

When you take it for a test drive listen out for any clonks from the suspension and if you have any doubts get a mechanic to check it over. As it's been brought in from the UK it's probably worth getting a history check through Cartell.ie as well to make sure of the low mileage.

Finally, the price isn't bad, but without a trade-in you should be haggling. Start at €22,750 and see what they say. There are several on the market around the same specification and value so don't be afraid to walk away.

Let us know how you get on.

Expert answer

Hi John,

As discussed via email, you need to determine that a) the electric fuel pump in the tank is working and b) that fuel is getting to the engine. These are intricate jobs that only a qualified mechanic should attempt. Given that your car was rear-ended, it's highly likely that the issue is related to the fuel pump in the tank.

Failing all that get an auto-electrician to go through the relevant fuel pump relays and fuses.

Hope you get sorted.

Expert answer

Hi Justin,

Let's break it down into chunks. First of all, safety. Here are the crash test results from Euro NCAP:

Skoda: five stars on new system

Saab: five stars on old system

Volvo: four stars on old system

Looks like the Volvo loses out there, though it's a safe car by most standards.

In terms of reliability, the Skoda has no reported issues. The Saab doesn't fare so well, with plenty of electrical issues and problems with the suspension. Check for uneven tyre wear and that all the switches are working - every single one. The Volvo is a little better, but has a few known problems, with random electrical gremlins and several recalls. If you're serious about that one get confirmation that the recall work has been completed. Also, it should have its timing belt, tensioners and pulleys changed every four years so best to check that it has been done.

Assuming you're looking at the 105hp Superb, then the combined cycle consumption was quoted at about 5.7 litres/100km (50mpg) and it is a frugal car. The 150hp Saab uses a fraction more fuel (5.8 litres/100km) on the combined cycle, while the 136hp Volvo also uses 5.7 litre/100km.

So in summary, for us it would be between the Skoda and the Volvo. They're both comfortable and spacious, though we'd trust the reliability of the Superb more given the data.

Hope that helps.

Expert answer

Hi Linda,

Honda undoubtedly has an enviable reputation for reliability, but the 5 Series BMW is one of the company's most reliable models. The current generation has only been in production since 2010 so it isn't old enough for us to have a lot of reliability data as yet, but its predecessor fared very well with only a few minor issues and electrical faults early in the model's life. It has since proven to be very robust. In terms of the engine, the BMW's 2.0-litre diesel has been around for a while and is made in large numbers, so there's nothing to worry about there either.

With my own money there's no doubt I'd go for the BMW.

Let us know what you end up doing.

Expert answer

Hi Paul,

Well one obvious answer, given the length of your commute would be to charge it in work during the week. Failing that, while the ESB will fit a box to the outside of your house, this would mean a lead being attached to your car from this and this of course could be open to vandalism. You will find that the number of on-street charging posts will dramatically increase over the next 12 months and there may be one near where you live with a special parking spot for an EV. 

Expert answer

Hi John, 

The Atkinson engine is a type of engine invented by James Atkinson in 1882. The Atkinson Cycle is where the stroke of the piston can very in length across the four cycles in a four-stroke internal combustion engine. The length of the stroke during the power cycle is increased to promote efficiency, but because this comes at the expense of a shorter intake stroke there is some loss of power and therefore this engine design is best suited for use in hybrid systems where the electric motor can make up for some of the loss of power. 

In conventional four-cycle petrol engines, fuel enrichment is sometimes necessary to cool the exhaust gases, preventing degradation or destruction of the catalytic converters. In an Atkinson cycle engine, compression and expansion are not symmetrical, and the valves close late, delaying compression. This creates a high expansion ratio for less compression, reducing intake and exhaust energy losses and converting combustion energy to engine power more effectively. As a result, the exhaust temperature is lower than that of conventional engines.

The current model Toyota Prius Hybrid uses a 1.8-litre Atkinson Cycle engine. Adopting the Atkinson cycle and a cooled exhaust gas recirculation system brings significant gains in fuel efficiency and emissions reduction.

Prius 1.8-litre Atkinson Cycle engine

Because the intake valves close late in an Atkinson cycle engine, compression is delayed. This creates a high expansion ratio for less compression, reducing intake and exhaust energy losses and converting combustion energy to engine power more effectively. As a result the exhaust temperature is lower than that of conventional engines. Cooled Exhaust Gas Recirculation reintroduces the cooled gas into the intake system, further reducing engine operating temperatures.

Other models to use Atkinson Cycle engines include the Lexus CT200h, Lexus RX 450h, Mercedes S400 Blue Hybrid