2004 IMPORT TECH REPORT

Transcription

1 2004 IMPORT TECH REPORT BY PAUL WEISSLER The return of the Wankel, a refined gas/electric hybrid and several all-new models highlight this year s offerings from the import carmakers. Creating totally different types of vehicles off a single basic platform is the most economical way for carmakers to cover a wide range of markets. The Japanese and Europeans have been honing this skill for years, and the 2004 model year is no exception. However, there also are some very new, technologically advanced vehicles coming to market. The Mazda RX8 brings the Wankel rotary engine back to America in a brand-new four-seat sports coupe with Saturn-inspired rear access doors. The Toyota Prius gas/electric hybrid has grown up and gets major technology upgrades that make it a midsize massmarket car. You ll be seeing other Toyota and Lexus cars in far greater numbers for many years, so their new technology is even more important to the technician. Examples include widespread application of OBD II-CAN (Controller Area Network) diagnostics, so a CANcapable scan tool is a must. And many Toyota/Lexus rear-drive automatics will not have a transmission fluid dipstick, so require a high-tech check & adjust procedure, plus a totally new fluid. The number of new models and new technology from European as well as other Japanese nameplates (even one domestic ) is awesome. The Jaguar XJ, Nissan Maxima and Quest minivan, Infiniti FX35 and FX45, Acura TSX and TL, BMW 5-Series and Chrysler Crossfire are just the standouts. You can t take a tech-service time-out. Mazda Mazda s new rotary engine doesn t develop quite as much horsepower as the twin-turbo of old, but at 207 hp for the base engine and 247 for the high-performance version, the coupe is quick. And with a price tag barely in the upper 20s, you ll see a lot more Mazda RX8 coupes than RX7 sports cars. Without the turbos and other hardware, the new rotary engine is more compact (same height as the transmission), so for vehicle weight distribution it s moved 2.4 in. further to the rear than it was in the RX7. This puts most of the engine weight past the centerline of the front axle, a design Mazda calls advanced front midship. Wasn t the rotary having problems with emissions? Yes, but the new engine has a significant design change: The exhaust ports were moved from the rotor housing (the chamber periphery) to the two large, flat side housings, where the intake ports also Chrysler Crossfire are located. This larger space permits larger ports, plus tailoring their shape for both optimum performance and lower emissions. Rotary engines respond well to multipath air intake systems, even more than piston engines. The base engine has a three-stage intake system controlled by three flap valves, the high-output a fivestage intake controlled by six flap valves. 24 December 2003

2 Jaguar XJ Toyota Prius Gasoline/Electric Hybrid The valve openings are computer-controlled according to engine rpm, with the intake runners getting shorter and straighter as rpm goes up. Some aspects of the engine may bring back memories. There are two spark plugs for each of the two rotor chambers. Those plugs have an iridium center electrode and platinum-tipped side (ground) electrode. There are two fuel injectors per chamber for the base engine, three for the high-output engine. The fuel injectors are not all the same. One has a 12- hole tip for ultra-fine atomization, and the other (or other two per chamber in the high-output) is a four-hole. The injectors are located in different places. With the high-output engine, the 12- hole is in the intermediate (inner) side housing, close to an intake port opening. The other two are in the intake manifold. With the base engine, both are in the intake manifold. The injectors pulse at different times, except at performance peaks, when both or all three inject at the same time. The sealing of the rotor was a problem in older models, but new materials and improved designs help December

3 The new rotary engine from Mazda, available in two stages of tune (207 and 247 hp), has two plugs per rotor chamber, as the four spark plug wires from the ignition module indicate. Exhaust ports join intake ports in the side housing of the new rotary, so good separation is possible. This photo shows the engine with one side housing removed. for the 2004s. Furthermore, the side location of both ports reduces the critical nature of the rotor apex seal. Rotary engines run at high speed, and the new RX8 engine develops peak horsepower at 8500 and can rev to 9000 rpm, so engine oil cooling is important. The standard engine has a single oil cooler and a system capacity of 6.3 qts. The high-output engine has twin oil coolers (one at each side of the radiator) and a 7.1-qt. capacity. The RX8 has electric-assist power steering a ball screw drive on a rack & pinion box, with computer control based on inputs from vehicle speed sensor and the input torque by the driver on the steering wheel. Toyota/Lexus OBD II-CAN diagnostics, which appears on many new Toyota/Lexus vehicles, can be read with a generic scan tool that has CAN capability. However, there s also an enhanced diagnostic mode, for which a CANdi plug-in module has been released. Vetronix makes the scan tool (a modified MasterTech) and the module, but the Toyota module is strictly for dealers at this time. Vetronix expects to release it to the aftermarket in the future, but a version of the software will appear in a future release for the aftermarket MasterTech, which gets its own generic CANdi module. As with other vehicle makers, OBD II-CAN diagnostics is on a phase-in at Toyota. For openers, we found it on the Lexus LS 430, plus a number of Toyota/Lexus products with the 3.3L V6 engine, and the new Prius gasoline/electric hybrid. One objection voiced about the Prius is that you can get it serviced only at a Toyota dealer. Okay, the big 201- volt battery pack is warranted for 8 years/80,000 miles, which means fewer aftermarket service appointments for a car that was introduced here in However, there are belts, hoses, bulbs, spark plugs, brakes, fluids, filters, air conditioning, even a conventional 12- volt battery and cables. There are about 50,000 Priuses on the roads here, admittedly not a great deal, but there s also a brand-new model for 2004, sized between Corolla and Camry, and still priced at about $20,000. Not only is the 2004 Prius larger, but average fuel consumption was reduced 15%, to an average of 55 mpg (in warm weather), so Toyota believes that with the pricing, it can sell the Prius as a mainstream car. Incidentally, an aftermarket service demand is developing out there, and maybe it s time to jump in. Toyota has other hybrids on the way (Lexus RX 330 and Toyota Highlander), Honda has its Civic hybrid on the market, there s a hybrid truck coming from GM this winter and the Ford Escape hybrid will be out next year. The new Prius has a physically smaller hybrid battery pack, but at over 200 volts, it s as powerful as its predecessor, thanks to a new battery design. In addition, a boost converter can raise voltage to 500, giving the car a lot more performance flexibility. Yes, the Prius is different. Not only does the 2004 model use braking energy to recharge the hybrid battery pack, but the braking itself is electronically controlled. A computer calculates the required braking force based on pedal pressure, then applies a combination of brake hydraulic pressure and regenerative braking force on a motor generator. However, the pedal pressure is 26 December 2003

4 Overlap (Intake Port Open Before Exhaust Port Closes) No Overlap Exhaust Gas The illustration of the previous Mazda rotary engine (left) shows how exhaust gases can escape from the rotor chamber exhaust port to the side housing intake port because of the rotor overlap. The new design (right) shows how the rotor covers the side ports, so exhaust gases cannot escape. Peripheral Exhaust Exhaust Port Rotor just a pressure signal to the antiskid computer under normal braking. The actual pressure comes from what used to be the booster pump, computermodulated to the wheel brakes. In case of a pump failure, of course, pedal pressure goes straight through to the wheel brakes. When you first start working on a Prius, you ll want to play it safe, and that means unplugging the hybrid battery pack first. As with the previous model, turn off the ignition, remove the trunk compartment carpeting and panels for access to the battery pack, which is just behind the rear seats. Locate a safety plug on the left side of the pack, lift it up and pull it out. The headlamps and other 12-volt accessories are powered by an auxiliary 12-volt battery. It s in the same location as the hybrid pack, but hidden by the air duct of the hybrid pack cooling system, a location chosen to save space. With all the electronics in the area, this battery is a shielded design, and the replacement unit should be, too. There s a battery boost terminal in the powertrain compartment. The old Prius had a combination radiator and condenser one part with two heat exchangers and a separate Side Exhaust Exhaust Port Rotor If the chart at right is missing, please circle #14 on the Product Information Card on page 65. Unburned Gas Trochoid Unburned Gas Trochoid In the previous rotary engine design (left), with the exhaust port in the rotor chamber periphery, any unburned gas from combustion is moved by the rotor tip and escapes into the exhaust. With the side exhaust port (center and right), the rotor covering the exhaust port prevents this, and the unburned gas is moved to the start of the next intake stroke. 28 December 2003

5 radiator for the hybrid electric system s power inverter. The new model has a single cooling module that combines all three, which are held together by brackets, so maybe replacement parts will eventually become available. The old Prius had to restart the engine to turn on the a/c. The 04 model has an electric motor-driven a/c compressor, so the engine can be shut down much more often. That s a big contributor to real-world fuel economy, but doesn t affect the EPA numbers, which are tallied with the a/c off. Keep in mind that the compressor is spun by a 201-volt AC motor, not the 12-volt auxiliary battery, so it won t run with the safety plug removed. The compressor still is mounted on the engine, but don t look for a drive belt pulley. The 1.5L four-cylinder engine develops 76 hp (up from 70), and its cooling system has a new Toyota pink antifreeze/coolant, recommended for a 100,000-mile replacement and at 50,000-mile intervals after that. This is based on maintaining a topped-up system, of course. You ll also find this new coolant on many other 2004 Toyota/ Lexus products. Can t tell pink from red, the conventional Toyota antifreeze color? Check the owner s manual. The Prius is in the group of vehicles classified as PZEV (Partial Zero Emission Vehicle) by California. That means EVAP (fuel vapor) emissions have to be effectively zero. So you ll find a permanent carbon filter to absorb engine-off hydrocarbons in the air filter housing. And the emissions system carries a 15-year/150,000-mile performance warranty. There s also a PZEV Camry four-cylinder for That carbon filter, incidentally, is in some non-pzev Toyota/Lexus models, too, where it contributes to reduced EVAP emissions. Toyota has increased displacement of the V6 from 3.0 to 3.3 liters, which gives it a lot more punch 225 hp, as opposed to the previous 198. You ll see it in two heavily redesigned models, the Solara and the Sienna minivan, plus the Lexus ES and Toyota Camry. Toyota also has a new automatic transmission fluid for worldwide use, Photo: Paul Weissler It looks like there s an air duct and an electronic black box on the right perimeter of Prius trunk. Well, between the two and behind them is a hint of that 12- volt auxiliary battery, which powers the headlights and other accessories. Carbon Filter Air Cleaner Cap Air Cleaner Element The filter built into the air cleaner cover on some Toyota/Lexus models is a hydrocarbon trap to help reduce engine-off fuel vapors to near zero. a low-viscosity oil for better cold driveaway. Toyota warns that if you use conventional fluid in severely cold weather, the vehicle may not move until the fluid is warm, which could take a few minutes. For 2004, the new fluid applies only to rear-drive systems, and just as important, if one needs fluid, there s no dipstick and fill tube. The new fluid fill system is found on the Lexus LS 430 sedan and two SUVs the GX 470 and LX 470 but don t be surprised when you encounter it in the near future on other Toyota products. Okay, you ve seen this before on some GM automatics, but the Toyota add-oil procedure designed for super accuracy is very different, even for small top-ups. There s a refill plug and an overflow plug, but you can t just add to the refill and look for an overflow. Those are merely among the first steps for a major addition, such as after removal of the oil pan. For a small addition, there s a multistep procedure that begins with jumpering two terminals of the underdash diagnostic link connector (three terminals, if the vehicle is equipped with air suspension), then going through a quick-shifting operation to warm up the fluid. Toyota also is using a tire pressuremonitoring system that does not rely on in-wheel pressure sensors. It uses the antilock brakes wheel speed sensors, but has a sophisticated computer strategy that looks at two aspects of the sensor signals. If new tires or December

6 Refill Plug Proper Level This illustration of the rear-drive automatic transmission used on Lexus LS 430 models and other Toyota products shows the overflow and refill plugs. Despite the absence of a dipstick and fill tube, you can t just pour fluid into the refill and look for overflow. There s a complex procedure, using jumper wires at the diagnostic link connector and a shifting procedure to warm up the fluid. wheels are installed, or when the tires are rotated, the system must be initialized using a reset button on the dashboard and the instrument panel warning light. Mercedes-Benz The newest model engineered by Mercedes carries a Chrysler nameplate the two-seat sport coupe Crossfire. It s based on the CLK/SLK platform, with a 94.5-in. wheelbase (same as the SLK), and an overall length of 160 in. Under the hood is the familiar 215-hp three-valve 3.2L V6, with its two-plugs-per-cylinder design. There s a choice between a six-speed manual or five-speed automatic. At about $9000 less than a comparable Mercedes, it s a bargain. The tires are Z-rated (ultra-high-performance) Michelins, on 18-in. wheels Low Tire Pressure Warning Light Overflow Plug in front and 19-inchers in the rear. Mercedes introduced a seven-speed automatic transmission that s available on the E-Class 500 V8 and both S-Class V8s. It has the ability to skip a gear if the throttle position provides the necessary signal to the powertrain computer. So if you find it s downshifting from 4th to 2nd gear, 7th to 5th, etc., that s normal. Of course, if the gear skips aren t occurring at reasonable times, the TPS certainly could be suspect. The torque converter clutch can be engaged in all seven gears, not just a few top gears, another normal feature of which you should be aware. And you may be seeing a lot more Mercedes sedans and wagons with 4MATIC all-wheel-drive. The price for the AWD system was lowered substantially on 2004 C-Class models, and it s Tire Pressure Warning Standardization Switch This is the tire-monitoring system reset light on the dashboard of the Lexus LS 430 and RX 330. When all tire pressures are adjusted to specs following tire rotation or replacement, turn on the ignition, then press the reset button until the instrument panel tire-pressure warning light blinks three times. been made available as an option on E- Class and S-Class vehicles. It s very caroriented a single-range transfer case. Volvo Volvo s image is safety, not performance, but the new S60R sedan and V70R station wagon both all-wheel-drive models get a turbocharged version of the 2.5L inline five-cylinder, which develops 300 hp and 295 ft.-lbs. of torque with the six-speed manual (a specific Volvo transmission) and is held to 257 ft.-lbs. of torque with the five-speed Aisin automatic. Both are transverse front-drive models, and although the inline Six is used on nonturbo models, there just isn t an automatic transmission that can tolerate any more torque, so Volvo stuck with the five-cylinder. In fact, the four-speed automatic on naturally aspirated models couldn t even take as much torque as the Aisin. The 2.5 five-cylinder engine has two in-series intercoolers for a twinturbo system that operates at a peak of 15 psi. One is between the radiator and the condenser, the other below them, just behind a below-bumper air intake. The S60R and V70R also have a sophisticated electronic suspension system, with the fastest-reacting shock valves available anywhere just a few milliseconds, with a maximum of about 10mS from closed to fully open. Of course, fully open is just.012 in., but there are about 1100 different positions the valves can assume, under control of a high-speed Motorola computer, with signals from two front-suspension vertical accelerometers, two rear-suspension height sensors and three body accelerometers (two vertical, one horizontal-and-vertical). Add in a high-speed CAN link from the powertrain and stability/traction system (computers, steering and yaw sensors) and there s a lot of information for ride control. The shocks are made by Monroe, but with valves made by Ohlins, which also makes racing suspensions. Ohlins shocks would have been too expensive, but the valve is the heart of the system, so the result is a racing suspension at a medium price. The control panel has a switch that permits the driver to select 38 December 2003

7 Torque Converter Lock-Up Clutch With Damping Elements Oil Pump With Shift Actuators, Multiplate Clutches and 3 Planetary Gear Assemblies Parking Lock to Drive Wheels To Shift Lever From Engine Control Unit With Solenoid Valves, Electronics and Sensors Built Into the Sump Torque Converter High-Speed Solenoid Valves for Control of Shift Actuators Electronics for Demand- Dependent Control of Shifting Action The new Mercedes seven-speed automatic is the world s first. Installed on most E-Class and S-Class V8s, it can engage the torque converter clutch in any gear, and skip gears when appropriate. Comfort, Sport and Advanced settings, in addition to the automatic control. And it s all seamlessly integrated with the AWD system. Jaguar The new top-of-the-line XJ features the first-ever all-aluminum monocoque with hardly a weld. Previous aluminum chassis simply have had aluminum body panels attached. In a monocoque, the chassis and body panels all come together to form a single structure, which, in fact, gets much of its strength when it s baked in the paint ovens. The XJ monocoque is riveted (3200 self-piercing rivets) and glued (394 ft. of epoxy). Aluminum vehicles pose an electrical problem: Except on some aluminum castings, the metal is too thin and soft to provide a durable grounding point. As on the Audi A8, the Jaguar XJ has welded-on nuts to make the ground connections. Although most body panels are part of the monocoque, the front fenders and the front section of the chassis are bolt-on parts, for easier replacement in case of an accident. The XJ is powered by a 4.2L V8 derived from the 3.9 V8 used in the Jaguar S and Lincoln LS. The naturally aspirated version develops 294 hp and 303 ft.-lbs. of torque. The numbers on a supercharged edition are 390 and 399, respectively. The transmission is a six-speed ZF automatic, but don t bother looking underneath or underhood for the transmission control module. It s a Bosch unit integrated with the electrohydraulic controls inside the transmission. Nissan/Infiniti You might think Nissan has just one V6 and one V8 engine the 3.5L V6 and 4.5L V8 made in several stages of horsepower tune. Well, that s true, but when they re put into very different vehicles (with the V6 going both transverse and north-south), how much more does Nissan need? And if you re a service tech, you appreciate the familiarity of the underhood, even if intake and exhaust systems, cam timing, etc., are different for the specific stages of tune. The new Maxima is transverse front-drive like all Nissan-brand sedans and minivans, and the carbased Murano SUV. The Maxima gets just 10 more hp (up to 265), is a few inches longer and gets an optional six-speed manual or five-speed automatic (the four-speed automatic is on the lower-cost models). The new Quest minivan is all-new and it s big. This one is on a 124-in. wheelbase (204 in. overall, which is in. longer than the old model) and it has 144 to 148 cu. ft. of cargo volume (44 more than the old model). The Infiniti FX35/FX45 is anoth- December

8 The Volvo S60R and V70R have a 300-hp version of the inline five-cylinder. The engine has a twin-turbo setup and dual intercoolers one between the radiator and condenser and one below, behind the front fascia air intake. er car-type SUV (sort of a big brother to the Nissan Murano), and like all Infinitis today, it s basically rear-drive (all-wheel-drive optional on FX35, standard on FX45), and the base engine is the 3.5 V6 rated at 280 hp. The 4.5 V8 is rated at 315, compared with 340 for the M45 sports sedan, in which it develops 333 ft.-lbs. of torque (4 more than the FX45). The AWD system has an electronically controlled multidisc clutch, and will be offered on the G35 sedan, as well. Welded Stud Bolt-On Front End Riveted & Glued The Jaguar XJ s all-aluminum monocoque is riveted and glued; there are no welds except for a handful of cosmetic locations. Most electrical grounds are provided by welded-on nuts and studs. Front fenders and a front-end safety member are bolt-on units, for easier repairability following an accident. Honda/Acura The Acura division gets the new cars this fall. One is the TSX, and if it looks like a super-premium Accord, that s because it is. The engine is a 200-hp version of the 2.4L Four, and because it has a longer stroke than the 2.0L Four in the Acura RSX, it gets better torque (166 ft.-lbs. vs. 142). Honda obviously made a large investment in upgrading the Accord s suspension, because the handling is superior and the ride is far better damped. The trans- Photos: Paul Weissler mission is a six-speed manual or fivespeed automatic. The new TL is basically a refined, evolved version of the previous model, which reflects Acura s ability to continually improve its engines. The interior is more luxurious and the technology is up-to-date, including the first use of hands-free telephone connectivity with Bluetooth wireless. However, this luxury car also is available with a six-speed manual, so Acura seems to be aiming at a performance-luxury audience. The 3.2L V6 develops 270 hp and 238 ft.-lbs. of torque, notable improvements over the 225 hp and 216 ft.-lbs. of the previous engine. With such features as cold air induction and the use of many new internal engine parts, the new 3.2 V6 clearly is a further development of the 260-hp Type S series engine available last year. In addition, it has close-coupled catalysts in exhaust manifolds at the cylinder heads to meet California LEV-II/ULEV emissions standards. The flywheel with the six-speed manual transmission is a dual-mass design. For those who just want the luxury, there s also a five-speed automatic, of course. The aluminum block is a new design, with cast-in-place iron liners. The liners themselves are made with a centrifugal spin-casting process that Acura says will produce stronger, lower porosity liners in a thin-wall design. The engine has the Honda threerocker setup for valve lift control, which allows each of the intake valves to be controlled by its own low-speed cam lobe. (This promotes swirl in the chambers.) The simpler, two-rocker design limits the engine to a single low-speed cam profile for both intake valves. Tuneup for the 3.2 V6 is scheduled for 105,000 miles, but this engine has a timing belt, and its replacement is part of the tuneup procedure. This report is kind of a quick scan that s intended to alert you to some of the new procedures you need to incorporate into your service routines. Visit to download a free copy of this article. 40 December 2003