En septembre, les immatriculations de voitures ? motorisation essence ont bondi de 25?%, alors que celles ? motorisation diesel se sont affaiss?es de pr?s de 5?% pour un march? g?n?ral en faible hausse (+3,4 %). Les conducteurs commencent donc ? se reporter massivement sur les motorisations essence, m?me si l'on reste tr?s loin du d?but des ann?es 2000, quand seulement un v?hicule vendu sur deux ?tait un diesel, selon le cabinet d'?tude Inovev.
Plusieurs raisons expliquent ce ph?nom?ne. D?but 2012, lors du lancement de sa citadine 208, qui d?tient une importante part de march?, Peugeot ne pr?sentait pas de motorisation essence... Les premiers moteurs essence ne sont apparus qu'au second semestre. D?s lors, par un effet de base statistique, les immatriculations de la 208 diesel ont chut? de 45?% au premier semestre, ce qui a en toute logique d?form? les statistiques g?n?rales. Le m?me ph?nom?ne touche la Clio IV, ?galement lanc?e d?but 2012, mais avec une offre essence. La part de la motorisation diesel de ce mod?le est en recul de 32?% sur un an.
Le?d?bat sur la nocivit? du diesel semble avoir pes? sur les ventes. En annon?ant clairement son intention de r??quilibrer la fiscalit? des diff?rents carburants, et donc d'augmenter ? terme le prix du diesel, le gouvernement oriente le march?, une voiture neuve ?tant g?n?ralement achet?e pour une longue p?riode en France. Enfin, le lancement par les constructeurs de moteurs essence extr?mement performants d'un point de vue consommation, a contribu? ? r?orienter les acheteurs vers ces offres de motorisation au d?triment du diesel.
Lire l'interview d'Anne Hidalgo : "Mon plan contre le diesel ? Paris" (lien Abonn?s)LES PETITES VOITURES EN PREMI?RE LIGNE
De m?me, les constructeurs commencent ? r?viser leurs perspectives pour leur offre de petites voitures. Apr?s l'Adam d'Opel, qui n'offre pas de motorisation diesel, c'est la prochaine Micra, la citadine de Nissan, qui en sera priv?e. Ford a pour sa part d?cid? d'arr?ter la production de bloc diesel pour sa Ka, une mini-citadine. Et en 2014, les futures mini-citadines de PSA (108, C1), de Toyota (Aygo) ou de Renault (Twingo) seront 100?% essence. Avec la nouvelle norme "Euro 6", qui entre en vigueur en septembre 2014, doter ces petits v?hicules d'un bloc diesel reviendrait beaucoup trop cher, car cette r?glementation impose la mise en place d'un proc?d? d'?limination des oxydes d'azote (Nox).
Le dispositif d?ploy? par de nombreux constructeurs, le Selective Catalytic Reduction (SCR) est ? la fois cher et lourd ? mettre en place, ce qui disqualifie les plus petits v?hicules. D?s lors, les seuls segments o? il restera rentable de d?ployer du diesel sont ceux des voitures compactes, des berlines, des monospaces et autres 4 x 4 qui font plus de 20 000 km par an. Le prix de ces v?hicules est compatible avec le d?ploiement de ces nouvelles technologies.
Cette nouvelle orientation du march? sera particuli?rement suivie par PSA Peugeot Citro?n et Renault. 60?% de leurs v?hicules vendus en Europe sont aujourd'hui ?quip?s d'un bloc diesel. Par comparaison, Volkswagen vend seulement la moiti? de sa production sous moteur diesel et Fiat ? peine plus de 40?%... Une chose est s?re pour tous les observateurs du march?, la part du diesel va baisser. Pour Inovev, cette part, actuellement de 55?% en Europe, devrait redescendre sous la barre des 50?% d'ici 2016-2017.?
The S7 hatchback, above, is a more conventional steel-body car than the S8, which has an aluminum space frame. More Photos »The state of the internal-combustion art has never been more artful. Direct fuel injection, variable valve timing, computer-controlled ignition systems and a hundred other technologies have become tools for shaping how an engine performs. Engineers can add torque here, subtract it over there, let the engine rev at one point and hold it back at another. This is a new artistic medium, and Audi’s latest V-8 engine is a masterpiece. Called the EA824 inside Audi, and marketed as the 4.0 TFSI V-8, it’s a densely packed engine less than 20 inches long that overachieves relative to its 4-liter displacement. TFSI stands for Turbo Fuel Stratified Injection, and right now internal combustion doesn’t come better than this. I drove two 2013 Audis equipped with different versions of the EA824. In July, my nephew and I took the large 520-horsepower all-aluminum S8 sedan ($125,995 as tested) on a blitz from Dallas to Oklahoma and across the Texas panhandle, all the way home to Santa Barbara, Calif. Then, a few weeks later, my wife and I drove the slightly smaller, sleeker, steel-body 420-horsepower S7 ($94,570 as tested) up the California coast to San Francisco and back. On the long, often empty, straights of Interstate 40 across the Great Plains, the S8 was outrageously serene. As we cruised through sudden cloudbursts, surprise hailstorms and blistering heat over three days, it pushed forth with only slight differences in tire noise to indicate whether we were moving across water, ice or broiling asphalt. Even on lonely stretches of open road, as our speed crept inadvertently toward three digits, there was barely a change in the wind’s whistle. This is Audi’s most capable and powerful large sedan, and it is built to ingest continents. The family of A8 sedans, of which the S8 is the highest performer, includes standard and stretched L versions (with wheelbases of 117.8 or 122.9 inches), with powerplants ranging from a turbodiesel V-6 to an outrageous 6.3-liter 12-cylinder. All of the A8s and the S8 are built with an all-aluminum space-frame structure that has been the car’s hallmark technology since the first-generation sedan of the mid-1990s. The high-style, low-slung S7 has a predatory countenance. There’s something empowering about simply ducking under the low roof and into the thickly bolstered driver’s seat, as if you’ve transformed from a weakling into a Charles Atlas muscleman without all that pesky weightlifting. But the S7 is a more conventional machine than the S8. It’s a hot-rod version of the A7 hatchback, which itself is a derivative of the more upright A6 sedan. The structure is ordinary steel and the 114.7-inch wheelbase is the same as the A6’s. Unfortunately, the S7’s squashed but stylish fastback roofline compromises headroom, and the rear legroom isn’t impressive either. Regular A7s are available with the same turbocharged diesel and supercharged gasoline 3-liter V-6s that are found in the A8. But new for 2014 is an even more radical RS7 that uses a version of the EA824 rated at a loopy 560 horsepower. With a base price of $105,400, it starts out $25,200 more expensive than the 2014 S7. That’s $25,200 that could be used for other important things. Like bail. Slicing through central California, where the weather is always perfect, I swear that my wife’s pupils dilated noticeably when she first dipped into the S7’s accelerator pedal. The S7 may give up 100 horsepower to the S8 — at least according to Audi’s suspiciously conservative ratings — but 420 horsepower is still some 2.4 times the rating of her Kia Sorento. Power may be corrupting, but it’s also empowering, liberating and fun. Forget all the navigation systems, radar-controlled cruise systems and even the Wi-Fi connectivity built into both the S7 and S8. All that is stuff you can find in other luxury performance cars. Other manufacturers are even adopting all-wheel drive similar to Audi’s once novel but still brilliant quattro system. What those other cars don’t have is the EA824.
