It should really be the Fusion +, of course, but even Ford sometimes uses the word rather than the arithmetical sign. Anyway, this is the top-spec Fusion, with a rather neat fold-down roof-mounted screen for the entertainment system which has DVD, Playstation and MP3 capability.The idea of all this, of course, is that children can occupy themselves in the rear seats (a remote control and two sets of earphones are provided) without either yawning their heads off, asking how much more of this seeming never-ending journey to Granny's they still have to suffer, or causing an uproar which upsets their more delicately balanced parents sitting in front.There are a few more things above the standard Fusion specification too. The Plus has some modest bits of exterior body styling kit as well as a revised front grille, and it's fitted with seven-spoke 16" alloys instead of wheels an inch down in size. It offers a satin aluminium insert for the gear lever knob, an extra 12-volt power point in the rear and darkened privacy glass for all the windows aft of the B pillar, plus a couple of close-fitting stowage pockets at the front and the left-hand side of the driver's seat, which handily adjusts for height.The front passenger's seat folds down to provide a picnic or work surface, and there's also a multifunction "activity console" for the rear seat, although the one in the test car seemed to have gone walkabout somewhere.We've done several reports on the Fusion, but this was our first long-distance test of the 1.6-litre petrol-engined Plus version. Buyers who choose this model obviously want the entertainment package, but they will also have reckoned that the 1.4-litre is not a vivid performer, and they won't be fans of diesel, however effective and particularly how economical the PSA/Ford 1.4-litre turbo diesel may be.That's all fair enough. The 1.6-litre petrol model is a pretty decent performer, although you have to bear in mind that the Plus, on its larger tyres and with its tiny amount of extra weight, loses 0.8 of a second on the official 0-62mph sprint to the Fusion 3.Even in Plus form, the Fusion is a car which doesn't really hit the spot for design either outside or in the passenger cabin, and I still can't believe that the trim textures are the best Ford could have come up with.But it's a very practically laid-out car, making good use of the taller-than-Fiesta bodywork and providing generous foot room under the front seats. There are plenty of small stowage spaces, and one major advantage of the Fusion is that it has an impressive load volume, in the case of the Plus with full carpeting.So I can certainly see it as the family car featured in Ford's promotional material, with space to take a pile of weekend sport or leisure kit. It's easy to drive around town and park, and the seating positions are a convenient height for older owners with stiffer joints. Yet I once had to listen to a Ford person's private opinion that in the long run the Fusion was likely to be thought of more highly as a Motability vehicle than anything else.Covering several hundred miles in the test car made me think there's rather more to it than that. Admittedly, Ford could have engineered in things like a more impressive clunk when the doors shut, but this is a car which isn't just for pottering round town or acting as transport for semi-geriatrics.Out on the open road the 1.6-litre petrol engine pulls strongly enough on long motorway climbs, and once you get on to more winding minor roads you remember that Ford's chassis engineers are at their best when dialling in handling and ride characteristics to cars of this general size, high-set ones as well as conventional superminis.However, this was also the first test car of any make which let us down because of a fault in the throttle system. When it was started up again after a mid-afternoon stop, a warning came on that there was a malfunction in the electronic acceleration control, and advised me to get the car to a dealer as soon as possible.Actually, I struggled the 45 or so miles back to CARkeys HQ, but it wasn't any fun, even though the get-you-home system did let the Fusion go faster than the 19mph mentioned in the handbook. It was completely gutless, though, and any kind of upward gradient was a real embarrassment. At the next attempt to start it, everything worked OK, but since we had no idea when the trouble might recur, we didn't do the extra miles for a Second Opinion this time round.