Engine Control Units A look at technology in the Automotive Industry

Introduction BACKGROUND –History –Computers & Vehicles Today ADVANTAGES OF COMPUTERS IN VEHICLES PERFORMANCE MODIFICATIONS OF ON-BOARD COMPUTERS –Sensors –Fuel Injection –Air/Fuel Mapping CAREERS IN THE AUTOMOTIVE TECHNOLOGY INDUSTRY –ECU Programming –ECU Tuning –Race car engineering & Data Acquisition CONCLUSION QUESTIONS

History of computers in vehicles Introduced in vehicles in 1981 Emission standards forced automotive manufacturers to turn to computers to manage engine controls Let to Fuel Injection becoming standard on modern vehicles

Computers & vehicles today The majority of vehicles today equipped with at least one computer The Engine Control Unit (ECU) is the ‘brain’ of the vehicle. Standard ECU is approx 9” x 6” housed in a metal container with one connecting port at the end

Advantages of computers in vehicles settings can be changed in real- time, including settings to give the vehicle the best fuel economy possible More flexibility on settings being computer controlled No choke as in carbureted systems to restrict airflow in Electronic Fuel Injection (EFI)

Carbureted GM 350ci V8Fuel Injected GM 350ci V8 Carburetor Throttle body

Performance Modifications of on-board computers Sensors “If an ECU is the Calculator, then the sensors are the numbers you put in the calculator.” (Zimmerman) Crucial for the proper functioning of any engine Throttle position sensor

Performance Modifications of on-board computers Smart Sensors Perform calculations before sending information to the ECU Relieves strain on ECU for performing calculations, giving more processing power for other tasks Digital data transmission is less susceptible to noise than analog data transmission Smart sensor

Performance Modifications of on-board computers Electronic Fuel Injection Modern injection systems use electronics to manage how much fuel is sprayed by the injectors, how long the spray lasts, and when the fuel is sprayed. Amount of fuel to be sprayed depends on readings by the sensors Two main types of fuel injection: Throttle Body Injection (TBI) and Multi- Port Injection (MPI)

Performance Modifications of on-board computers Throttle Body Injection

Performance Modifications of on-board computers Multi-Port Injection

Performance Modifications of on-board computers Fuel Injection methods Three different methods of fuel delivery: batch, bank-to-bank, and sequential Batch –All injectors spray once every engine cycle Bank-to-bank –Half of injectors spray at 180°, other half spray at 360°. Sequential –Each injector sprays once every two engine cycles.

Performance Modifications of on-board computers EFI upgrades Most popular upgrades: –Injectors –Electronic high output fuel pump –Fuel pressure regulator –Sensors Performance can be increased by up to double original output by changing injectors Achieved by changing injector pulse to 50% of original specifications.

XFI – the future in performance SFI

Performance Modifications of on-board computers Air/Fuel Mapping Information that is needed by the ECU in order for the engine to run A ‘database’ of information on conditions and sensor readings to manage the air/fuel ratio. “Depending on the conditions based on sensor feedback such as coolant temperature, engine load, manifold pressure, engine speed to vehicle speed relationship and throttle angle, the ECU will look to a certain cell in the map for an instruction. This becomes even more critical when after market performance parts are used. For example, if a high performance exhaust system, and a high performance air filter is added, there is a possibility that the engine will run lean in certain parts of the map due to the increased air flow” (Neimi).

Performance Modifications of on-board computers

Editing Air/Fuel Maps Fuel and timing maps can be adjusted using custom software for the ECU Maps are downloaded onto a laptop and adjusted with the software New maps are then sent to the ECU and instantly a difference is noticed in the engine’s performance. “The beauty of EFI is that you can accomplish the same things without even getting your hands dirty. Fuel calibration can be accomplished with a stroke on a computer keyboard. In addition, many more parameters can be changed in a similar fashion. Timing curves, idle speed, cooling fan control, etc” (F.A.S.T.).

Careers In The Automotive Technology Industry ECU Programming Designing ECUs for automotive manufacturers Units are calibrated for emission standards and fuel economy Employed by automotive manufactures around the world

Careers In The Automotive Technology Industry ECU Tuning Similar to ECU Programming ECUs are edited instead of designed ECUs are calibrated for performance, not emissions Employed by performance shops and some aftermarket product manufacturers

Careers In The Automotive Technology Industry Race car engineering and Data Acquisition Requires ability to interpret data output from aftermarket ECUs, and recalibrate it to better settings than before ECU tuning knowledge is also required

Conclusion With the huge industry of Automotive Technology, there comes a need for skilled professionals to get the jobs done in maintaining these systems on vehicles. The demand for certified technicians will continue to grow as the number of complexity in automobiles continues to rise (Weatherly). Required education for a career in the field is a certified automotive technician with upgrading courses in electronics.

End of Presentation Questions?