Dramatic changes to the automobile have occurred over the last 35 years, including the addition of emission control systems, more fuel-efficient and,cleaner-burning engines, and lighter body weight. In addition to being lighter than body-over-frame vehicles, uni bodies offer better occupant protection by distributing impact forces throughout the vehicle.
Today's computerized engine control systems regulate such things as air and fuel delivery ignition timing, and emissions. The result is an increase in overall efficiency. All automobile engines are classified as internal combustion, because the burning of the fuel and air occurs inside the engine. Diesel engines share the same major parts as gasoline engines, but they do not use a spark to ignite the air/fuel mixture. The cooling system maintains proper engine temperatures. Liquid cooling is more efficient than air cooling and more commonly used. The lubrication system distributes motor oil throughout the engine. This system also contains the oil filter necessary to remove dirt and other foreign matter from the oil. The fuel system is responsible not only for fuel storage and delivery but also for atomizing and mixing it with the air in the correct proportion. The exhaust system has three primary purposes: to channel toxic exhaust away from the passenger compartment, to quiet the exhaust pulses, and to burn the emissions in the exhaust. The electrical system of an automobile includes the ignition, starting, charging, and lighting systems. Electronic engine controls regulate these systems very accurately through the use of microcomputers. Modern automatic transmissions use a computer to match the demand for acceleration with engine speed, wheel speed, and load conditions. It then chooses the proper gear ratio and, if necessary initiates a gear change. The running gear is critical to controlling the vehicle. It consists of the suspension system, braking system, steering system, and wheels and tires. Preventive maintenance involves regularly scheduled service on a vehicle to keep it operating efficiently and safely. Professional technicians should stress the importance of PM to their customers.
12">The automotive industry technological
The automotive industry technological leaps and over is constantly making big a century the automobile has been transformed from mere, transport to a technological marvel. Here's looking at the top technologies that have revolutionized the motoring world.
Microchip
Although few people realised it at the time, in the late '6os the microchip lifted motoring into the electronic ,age. That sliver of silicon, with its incredibly fine thatch of circuits and umpteen transistors, unquestionably stands as the single most influential development in the past 50 years. if not in the car's entire history. The way cars work changed forever, with ongoing realizations made progeny: by the microchip's progeny: the on-board computer and electronic control module. A computer manages the engine- continuously Checking its temperature, speed, diet, and spark - while also administering the cruise control, traction control, rev limiter and drive-by-wire throttle. Other sides of the electronic brain oversee the automatic transmission, trip computer, sound system, and climate control, not to mention the anti-tock brakes, dynamic stability system, brake-force distribution, airbag deployment and more. The body computer that locks the doors soon after the car is mobile may know to unlock them, switch off the engine and notify emergency services in the event of a serious crash. White the seatbelt has played an important role, the microchip has truly revolutionised the automobile industry.
50 TOP TECHNOLOGIES
COLLAPSIBLE STEERING COLUMN
Although the very real dangers presented by rigid steering columns were Known for many decades, it wasn't until the late 19150s that collapsible steering columns began appearing. All modern cars now feature a collapsible steering column which will collapse in the event of a heavy frontal impact to avoid excessive injuries to the driver. This safety feature became mandatory after activist Ralph Nader, in 1965, released 'Unsafe at Any Speed', a study that revealed the unsafe engineering of many American cars. Delphi's active energy- absorbing steering column absorbs various levels of energy based on occupant mass, seat belt usage, speed, and crash severity, helping to minimize driver injury in the event of an accident.
THREE-POINT SEATBELT
Volvo had the first safety belts in 1941 and it was their inventor Nils Bohlin who devised the three-point seatbelt. Volvo introduced the safety measure in 1959, standardising it in all its cars. Not only did the three- pointer afford unrivalled restraint, but its use was a quick, easy, one-handed operation. lt is now a standard safety device in all vehicles, with most countries making it mandatory for the front passengers to wear them. Although many improvements have been made to the webbing, mountings, latches and inertia reels, and belts have got smarter in relating to accident severity and occupant weight, the principle is as valid and valued as ever.
CATALYTIC CONVERTER
The biggest advance in the fight against noxious exhaust emissions,' cats' were developed in the US in the 196os. Fully effective only when scorching hot, converters' catalytic-coated interior scours the outgoing gas to neutralise harmful ingredients. Early two-way converters were filled with small 'pebbles' coated with precious-metal catalysers: platinium. rhodium and platinium. But these converters were heavy, restrictive to gas flow, and acted only on carbon dioxide and hydrocarbons, Subsequent closed-loop systems have three-way converters. Here the gas passes through a finely perforated block of coated substrate, which acts on the villainous oxides of nitrogen as well as CO2 and hydrocarbons, Since 1975, Delphi has produced more than 100 million catalytic converters.
UNLEADED PETROL
Leaded petrol was discovered in 1921by General Motors.GM researchers had been : testing fuel blends since 1916, trying to stop engine 'knock'. Knock was a problem that was preventing the development of higher efficiency, higher. Compression engines. It had to be phased out by government order, starting in the 1970s, for public health- reasons, due to expelled lead having an adverse impact on the environment and human health and also its incompatibility with catalytic converters. Most countries are now phasing out leaded fuel; different additives have replaced the lead compounds, giving rise to unleaded fuel
oxygen lambada sensor
An automotive oxygen sensor, also known as an o2 sensor, lambda probe, lambda sensor, is a small sensor inserted into the exhaust system of, a petrol engine to measure the concentration of oxygen remaining in the exhaust gas to control the efficiency of the combustion process in the engine, In most modern cars, these sensors are attached to the engine's exhaust manifold to determine whether the mixture of air and PetroI going into the engine is rich (too much fuel) or lean (too little fuel). This reading converts to an Electrical signal, via which the engine ECU leans or richens the mixture to maintain the optimum stoichiometric (aka Lambda) air-fuel ratio, for the best possible fuel economy and lowest possible exhaust emissions. The Delphi Wide Range Oxygen sensor measures the air/ fuel ratio of exhaust gases over a wide lambda range.
AIRBAGS
lnvented in 1952 by John W Hetrick, the airbag is an inflatable, flexible membrane or envelope that fills up with air or gas. Triggered by sensors, it takes a split second to inflate and cushion the occupants from hitting the insides of the car, in the event of an accident. It is also known as a Supplementary/ Secondary Restraint System (SRS), and was first offered in the 1973 model Oldsmobile Toronado. Many modern cars have multiple airbags on the doors, known as Airbag Curtains, to protect from side collisions. Many advanced technologies are being developed to tailor airbag deployment to the severity of the crash, the size and posture of the vehicle occupant, belt usage and how close that person is to the airbag module. Many of these systems will use multistage inflators that deploy less forcefully in stages in moderate crashes than in very severe crashes.
SEATBELT PRE-TENSIONERS
A pretensioner system pre-emptively tightens the seatbelt to prevent the passenger from jerking forward in a crash, First introduced by Mercedes- Benz in the 1981 S-Class, it, in the event of a crash, will tighten the belt almost instantaneously. This reduces the load on the occupant in a violent crash. Pretensioners are triggered by sensors in the car's body, and most use explosively expanding gas to drive a piston that retracts the belt. They also lower the risk of submarining, which is when a passenger slides forward under a loosely worn seatbelt.
SEATBELT LOAD LIMITER
Load Limiters help minimise the peak force that an occupant will undergo when restrained by the seatbelt in a severe frontal collision. Load limiters are integrated into the seatbelt retractor system and will at low seatbelt webbing to release in a controlled manner, This allows the body to move forward into the airbag and balance the absorption of the energy of the crash. The end result is a more controlled amount of force being exerted on the occupant's body and the reduction of belt- inflicted injury .
Disc Brakes
Experiments with disc-style brakes began in England in the 189os, with the first ever automobile disc brakes patented in 1902. But it was only in 1949 that they made their commercial appearance in a low-volume. Crosley Hotshot. Disc brakes offered greater stopping performance than drum brakes, including resistance to brake fade caused by overheating, and quicker recovery from immersion. They have now become common in most passenger vehicles, although rear wheels to keep coast and weight down. A recent advance is lightweight ceramic disc brakes which are highly heat and fade- resistant.
LAMINATED WINDSCREEN
After the outlawing of murderous plate-glass windows, the windscreen world was dominated until the 1960s by toughened glass, which shattered in relatively harmless granules when fractured. Although shatter-proof laminated windscreens were avaliable as a costly option on many vehicles, it was the Japanese who were the first to standardise triple-layer glass. This Left the rest to follow, many after several governments made them mandatory.
Automotive Servicing today's
Servicing today’s cars and trucks is much different than it was just a few years ago. Demands on the automotive industry to build more reliable, cleaner, safer, and mare fuel-efficient vehicles has greatly changed the way products are built, operated, and serviced. Today's automotive technicians must keep up with these changes. Electronic controls are part of nearly every system, from the engine and the ignition system to brakes and transmissions. Automobile mechanics who have not kept up with these changes have left or been forced out of the industry. This has resulted in a shortage of qualified technicians. This shortage comes at a time when more cars are on the road and, therefore, more cars need to be serviced. As a result, there are more excellent career opportunities for skilled and certified service technicians than ever before.
Why today’s automotive industry is considered a global industry.
When the first automobile rolled down a street over one hundred years ago, life changed. Only the elite owned one of these early horseless carriages, which were a sign of wealth and status. Today, an automobile is a necessity. Most Americans would have a difficult time surviving without a car. We need our cars and we need the automotive industry. Each year millions of new cars and light trucks are produced and sold in North America . The automotive industry’s part in the total economy of the United States is second only to the food Industry. Manufacturing, selling, and servicing these vehicles is an incredibly large, diverse, and expanding industry. Nearly thirty years ago, America’s “big three” automakers-General Motors, Ford Motor Company, and Chrysler Corporation-dominated the auto industry. That is no longer true. The industry is now a global industry. Auto makers from Japan, Korea, Germany, Sweden, and other European and Asian countries compete with U.S. companies for domestic and foreign sales.Several foreign manufacturers, such as Honda, operate assembly plants in the United States and Canada. Chrysler Corporation has merged with Mercedes-Benz to form a new company-DaimlerChrysler. No longer is Chrysler only a domestic car company; this merger has made it a global company. Many more mergers and acquisitions in the future will continue to create global automobile manufacturers. A number of car models are built jointly by the United States and foreign manufacturers. These vehicles are built in North America to be sold here or exported to other countries. Some of these joint ventures manufacture automobiles overseas and import the vehicles into North America. This cooperation between manufacturers and the public acceptance of imported vehicles has resulted in an extremely wide selection of vehicles from which customers may choose. This has also created new challenges for automotive technicians that are based on one simple fact: along with the different models come different systems.
The Technology Boom
The automobile started out as a simple mechanical beast. It moved people and things with little regard to the environment, safety, and comfort. Through the years these
concerns have been the impetus for design changes. A technical area that has affected automobile design the most is the same one that has greatly influenced the rest of our lives--electronics. Today's automobiles are sophisticated, electronically controlled machines. To provide comfort and safety, while still being friendly to the environment, these new machines use the latest developments of many different technologies-mechanical and chemical engineering, hydraulics, refrigeration, pneumatics, physics, and, of course, electronics. Because electronics play an important part in the operation of all automotive systems, an understanding of electronics is a must for all automotive technicians. The needed level of understanding is not that of an engineer; instead, technicians need a practical understanding of electronics. In addition to mastering the mechanical skills needed to remove, repair, and replace faulty or damaged components, today’s technician also must be able to diagnose and service electronic systems. Computers and electronic devices are used to control the engine and its support systems. Because of these controls, cars of today use less fuel, perform better, and run cleaner than those in the past.
Electronic controls also are used to activate shifting in transmissions, eliminate brake lockup in antilock braking systems (ABS), improve handling by controlling steering and suspension systems, and provide passenger protection and comfort. The amount of electronics used on cars and trucks is increasing with each model year.
Consider these facts:
About 80% of all functions on new cars will be controlled by electronics.
1) Antilock braking systems, now an option on many vehicles, will become standard equipment on nearly all cars. Some vehicles already use and others will use three or more different computers to control different systems on the car. Separate computers are used to control the engine, the transmission/transaxle, instrumentation and climate control, the suspension system, steering system, and antilock brakes. Vehicle diagnostic systems will anticipate break-downs, contact emergency road service, and guide technicians through the repair process. Brake lights will vary in size and brightness according to the pressure put on the brake pedal. Headlights will have moveable reflectors that will allow the lights to follow the curves in the road. In the near future, some model vehicles will have multiple video cameras to view the area all around the car eliminating blind spots, and an infrared system to provide good vision at night and in bad weather. Complex electronic circuitry is and will be used to control engine systems so that the engine’s exhaust will contain very low amounts or zero pollutants. Intelligent cruise control devices will combine speed control with braking. The vehicle’ brakes will be applied automatically to maintain safe distances between moving cars. The distance will be monitored by radar. Global navigation and satellite tracking systems allow the driver to avoid adverse traffic and road conditions by giving detailed travel routing. Hands-free driving will be made possible through controls embedded into highways.
2) There are many reasons for the increasing incorporation of electronics into automobiles. Electronics are based on electricity and electricity moves at the speed of light. This means systems can be monitored and their. mode of operation changed very quickly. Because they have no moving parts, electronic components do not wear. This means they last a long time and don’t require periodic adjustments. Electronic components are also very light. Reducing vehicle weight means improved performance and fuel mileage.
3) Right now, only the creativity of the designers limits the future use of electronics in the automotive industry. That creativity will shape the vehicles of the future. However, other factors will also influence the shape of the future and the use of electronics. One of the main factors has been and will be legislation. Throughout recent history, car manufacturers have responded to laws designed to make automobiles safer and run cleaner. These laws have pretty much dictated the way cars run and look. They have also changed the world of work for automotive technicians. As the manufacturers respond to legislation, new systems and components are introduced. With these come new learning requirements for technicians. Anyone desiring to be a good technician must update his or her skills to keep up with the technology A recently passed law, called On-Board Diagnostics II (OBD-II), has made life easier for technician. It gives all technicians a chance to repair the computer controls of all makes and models of cars. It does this by ordering the manufacturers to use a common system and common terms to describe it. This is a big change! For many years, each manufacturer took its own approach to computer controls. The result was nearly as many different systems as there were car models. In the near future, a third edition of OBD, OBD-III, will be passed which should further simplify a technician's life.
The Need for Quality Service
Vehicles will continue to become more complex; therefore, the need for good technicians will continue to grow. Currently there is a great shortage of qualified automotive technicians. This means there are, and will be, excellent career opportunities for good technicians. Good technicians are able to diagnose problems in both the simple and the complex systems of today's automobiles. Of course, after the cause of a problem has been identified, the system must be properly serviced or repaired .With the increase in the price of new cars came increased public demand for very reliable vehicles. The public also demands that when things do go wrong, they should be corrected the first time they take the vehicle back to the dealership-they expect the problem to be "fixed right the first time." This feeling also carries through to older vehicles, those out of warranty and serviced by someone other than the dealership. Paying for repairs and parts that don’t fix the problem is not something consumers want, nor should we expect them to. It is also not something that helps the reputation of technicians or the manufacturer of the vehicle. After all, who wants a vehicle that can’t be fixed or a technician that can’t fix problems. The primary reason some technicians are unable to fix a particular problem is simply that they can’t find the cause of the problem. Today’s vehicles are complex, which means that a great amount of knowledge and understanding is required to diagnose them. Today’s technicians must have good diagnostic skills. Individuals who can identify and solve problems the first time the vehicle is brought into the shop are those who are wanted by the industry. For them, there are many excellent opportunities .The high cost of electronic components and many mechanical parts has made the “hit-and-miss” method of repair too expensive. Too often, mechanics who do not understand how to properly troubleshoot an electronic system automatically replace its most expansive component-the computer. This often results in a very expensive wrong guess. Computers are very reliable. Normally, the cause of a problem in a computer system is the failure of an inexpensive switch or sensor, a poor electrical connection, or a bad mechanical part within the system. Proper diagnostic techniques are also important for finding what caused a vehicle to fail an exhaust gas test, especially an I/M-240 test. Technicians must be able to find the reason why the vehicle failed and correct the problem.
The Need for Ongoing Service
The use of electronic controls has not eliminated the need for routine service and scheduled maintenance. In fact, it has made it more important than ever. Although the computer systems can make adjustments to cover up some problems, a computer cannot replace parts that wear. A computer cannot tighten loose belts, change weak or dirty coolant, or change dirty engine oil. Simple problems such as these can set off a chain of unwanted events in an engine control system. Electronic controls are designed to help a well-maintained vehicle operate efficiently. They are not designed to repair systems. The computer, through its control devices, may attempt to compensate for a problem by making adjustments to the engine’s systems. As a result, the engine will run reasonably well, but its overall performance and efficiency will be lowered. Various maintenance procedures usually are performed according to a schedule recommended by the vehicle’s manufacturer. These maintenance procedures are referred to as preventive maintenance (PM) because they are designed to prevent problems. Scheduled preventive maintenance normally includes oil and filter changes, coolant and lubrication services, replacement of belts and hoses, and replacement of spark plugs, filters, and worn electrical parts . If a car owner fails to follow the recommended maintenance schedule, the cars warranty might not cover problems that result. For example, if the car’s engine fails during the period of time covered by the warranty, the warranty may not cover the engine if the owner does not have proof that the engine’s oil was changed according to the recommended schedule. Recently, many manufacturers have introduced 100,000-mile (160,000 km) engines. There are many misconceptions about what this term means. It doesn’t mean the engines will last 100,000 miles (160,000 km). Hopefully they will last much longer than that. It doesn’t mean these engines will not need maintenance for 100,000 miles (160,000 km). These engines still need to have their oil and filter changed on a regular basis. The basic premise behind calling an engine a “100,000 mile (160,000 km) engine” is simply that the engine does not require a tune-up during that time frame. This is only true if the engine is not abused and is properly maintained.
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