# Engine control unit > Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Engine_control_unit > Markdown URL: https://mediated.wiki/source/Engine_control_unit.md > Source: https://en.wikipedia.org/wiki/Engine_control_unit > Source revision: 1356086377 > License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) Computer that adjusts electronics in an internal combustion propulsion system Delco ECU used in General Motors vehicles built in 1996 An **engine control unit** (**ECU**), also called an **engine control module** (**ECM**),[1] is a device that controls various subsystems of an [internal combustion engine](/source/Internal_combustion_engine). Systems commonly controlled by an ECU include the [fuel injection](/source/Fuel_injection) and [ignition](/source/Ignition_system) systems. The earliest ECUs (used by aircraft engines in the late 1930s) were mechanical-hydraulic units; however, most 21st-century ECUs operate using [digital electronics](/source/Digital_electronics). ## Functions The main functions of the ECU are typically: - [Fuel injection](/source/Fuel_injection) system - [Ignition system](/source/Ignition_system) - [Idle speed](/source/Idle_speed) control (typically either via an [idle air control valve](/source/Idle_air_control_valve) or the [electronic throttle](/source/Electronic_throttle) system) - [Variable valve timing](/source/Variable_valve_timing) and/or [variable valve lift](/source/Variable_valve_lift) systems The sensors used by the ECU include:[2] - [accelerator pedal position sensor](/source/Electronic_throttle_control) - [camshaft](/source/Camshaft) position sensor - [coolant temperature sensor](/source/Engine_coolant_temperature_sensor) - [crankshaft position sensor](/source/Crankshaft_position_sensor) - [knock](/source/Engine_knocking) sensors - [manifold absolute pressure sensor](/source/MAP_sensor) (MAP sensor) - intake air temperature sensor - intake air [mass flow rate](/source/Mass_flow_rate) sensor ([MAF sensor](/source/Mass_flow_sensor)) - [oxygen (lambda) sensor](/source/Oxygen_sensor) - [throttle position sensor](/source/Throttle_position_sensor) - [wheel speed sensor](/source/Wheel_speed_sensor) ### Secondary Other functions include: - [Launch control](/source/Launch_control_(automotive)) - [Fuel pressure regulator](/source/Fuel_pressure_regulator) - [Rev limiter](/source/Rev_limiter) - [Wastegate](/source/Wastegate) control and [anti-lag](/source/Anti-lag) - Theft prevention by blocking ignition, in response to input from an [immobiliser](/source/Immobiliser) In a [camless piston engine](/source/Camless_piston_engine) (an experimental design not currently used in any production vehicles), the ECU has continuous control of when each of the [intake and exhaust valves](/source/Poppet_valve#Usage_in_internal_combustion_engines) are opened and by how much.[3][4] ## Early systems One of the earliest attempts to use such a unitised and automated device to manage multiple engine control functions simultaneously was created by [BMW](/source/BMW) in 1939 *Kommandogerät* system used by the [BMW 801](/source/BMW_801) 14-cylinder [radial engine](/source/Radial_engine) which powered the [Focke-Wulf Fw 190 V5](/source/Focke-Wulf_Fw_190#Fw_190_V5) fighter aircraft.[5] This device replaced the six controls used to initiate hard acceleration with one control; however, the system could cause surging and stalling problems.[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*] ## Use in motor vehicles In the early 1970s, the [Japanese electronics industry](/source/Electronics_industry_in_Japan) began producing [integrated circuits](/source/Integrated_circuit) and [microcontrollers](/source/Microcontroller) for controlling engines.[6] The [Ford EEC](/source/Ford_EEC) (Electronic Engine Control) system, which used the [Toshiba](/source/Toshiba) TLCS-12 microprocessor, entered mass production in 1975.[7] The first [Bosch](/source/Bosch_(company)) engine management system was the [Motronic 1.0](/source/Motronic#1.0), which was introduced in the 1979 [BMW 7 Series (E23)](/source/BMW_7_Series_(E23)).[8] This system was based on the existing [Bosch Jetronic](/source/Jetronic) fuel injection system, to which control of the ignition system was added.[9] In 1981, a [Delco Electronics](/source/Delco_Electronics) ECU was used by several [Chevrolet](/source/Chevrolet) and [Buick](/source/Buick) engines to control their fuel system (a closed-loop carburetor) and ignition system.[10] By 1988, Delco Electronics was the leading producer of engine management systems, producing over 28,000 ECUs per day.[11] ## Use in aircraft engines Such systems are used for many internal combustion engines in other applications. In aeronautical applications, the systems are known as [FADECs](/source/FADEC) (Full Authority Digital Engine Controls). This kind of electronic control is less common in piston-engined light fixed-wing aircraft and helicopters than in automobiles. This is due to the common configuration of a [carbureted](/source/Carburetor) engine with a [magneto ignition](/source/Magneto_ignition) system that does not require electrical power generated by an [alternator](/source/Alternator) to run, which is considered a safety advantage.[12] ## See also - [Air-fuel ratio meter](/source/Air-fuel_ratio_meter) - [Check engine light](/source/Check_engine_light) - [List of auto parts](/source/List_of_auto_parts) - [On-board diagnostics](/source/On-board_diagnostics) (OBD) - [Powertrain control module](/source/Powertrain_control_module) (PCM) ## References 1. **[^](#cite_ref-1)** ["How an Automotive Computer Works"](https://www.2carpros.com/articles/how-a-car-computer-works-pcm-ecm-bcm). *www.2carpros.com*. Retrieved 14 May 2023. 1. **[^](#cite_ref-2)** ["Toyota Prius - Engine Control Systems"](http://autoshop101.com/forms/Hybrid12.pdf) (PDF). *www.autoshop101.com*. Retrieved 14 May 2023. 1. **[^](#cite_ref-3)** Austen, Ian (2003-08-21). ["WHAT'S NEXT; A Chip-Based Challenge to a Car's Spinning Camshaft"](https://query.nytimes.com/gst/fullpage.html?res=9503E1DB1F30F932A1575BC0A9659C8B63&sec=&spon=&pagewanted=1). *[The New York Times](/source/The_New_York_Times)*. Retrieved 2009-01-16. 1. **[^](#cite_ref-4)** ["How Proportional Valve Control Module control the oil flow direction"](https://www.genndih.com/proportional-flow-control-valve.htm). *www.genndih.com*. Retrieved 2023-06-03. 1. **[^](#cite_ref-5)** Gunston, Bill (1989). *World Encyclopedia of Aero Engines*. Cambridge, England: Patrick Stephens Limited. p. 26. [ISBN](/source/ISBN_(identifier)) [978-1-85260-163-8](https://en.wikipedia.org/wiki/Special:BookSources/978-1-85260-163-8). 1. **[^](#cite_ref-6)** ["Trends in the Semiconductor Industry: 1970s"](http://www.shmj.or.jp/english/trends/trd70s.html). *Semiconductor History Museum of Japan*. Retrieved 27 June 2019. 1. **[^](#cite_ref-shmj-1973-toshiba_7-0)** ["1973: 12-bit engine-control microprocessor (Toshiba)"](http://www.shmj.or.jp/english/pdf/ic/exhibi739E.pdf) (PDF). *Semiconductor History Museum of Japan*. Retrieved 27 June 2019. 1. **[^](#cite_ref-8)** ["25 years of Bosch Motronic: Think tank under the bonnet"](https://web.archive.org/web/20060623123242/http://www.bosch.com/content/language2/html/3074_3184.htm). *www.bosch.com*. Archived from [the original](https://www.bosch.com/content/language2/html/3074_3184.htm) on 23 June 2006. 1. **[^](#cite_ref-9)** Probst, C. (27 November 1989). [*Bosch Fuel Injection and Engine Management*](https://books.google.com/books?id=0dumo4gAhK0C). Robert Bentley, Incorporated. [ISBN](/source/ISBN_(identifier)) [978-0-8376-0300-1](https://en.wikipedia.org/wiki/Special:BookSources/978-0-8376-0300-1). Retrieved 13 May 2023. 1. **[^](#cite_ref-10)** ["GM Emission Control Project Center - I Was There"](https://web.archive.org/web/20170703134757/http://history.gmheritagecenter.com/wiki/index.php/GM_Emission_Control_Project_Center_-_I_Was_There). *www.gmheritagecenter.com*. Archived from [the original](http://history.gmheritagecenter.com/wiki/index.php/GM_Emission_Control_Project_Center_-_I_Was_There) on 3 July 2017. 1. **[^](#cite_ref-11)** Delco Electronics Electron Magazine, The Atwood Legacy, Spring '89, page 25 1. **[^](#cite_ref-12)** *Pilot's Encyclopedia of Aeronautical Knowledge*. [Federal Aviation Administration](/source/Federal_Aviation_Administration). Wikimedia Commons has media related to [Engine control unit](https://commons.wikimedia.org/wiki/Category:Engine_control_unit). v t e Internal combustion engine Part of the Automobile series Engine block and rotating assembly Balance shaft Block heater Bore Connecting rod Crankcase Crankcase ventilation system (PCV valve) Crankpin Crankshaft Core plug (freeze plug) Cylinder (bank, layout) Displacement Flywheel Firing order Stroke Main bearing Piston Piston ring Starter ring gear Valvetrain and Cylinder head Flathead layout Overhead camshaft layout Overhead valve (pushrod) layout Tappet / lifter Camshaft Chest Combustion chamber Compression ratio Head gasket Rocker arm Timing belt Valve Forced induction Blowoff valve Boost controller Intercooler Supercharger Turbocharger Fuel system Diesel engine Petrol engine Carburetor Fuel filter Fuel injection Fuel pump Fuel tank Ignition Magneto Compression ignition Coil-on-plug Distributor Glow plug Ignition coil Spark plug Spark plug wires Capacitor discharge ignition Engine management Engine control unit (ECU) Electrical system Alternator Battery Dynamo Starter motor Intake system Airbox Air filter Idle air control actuator Inlet manifold MAP sensor MAF sensor Throttle Throttle position sensor Exhaust system Catalytic converter Diesel particulate filter Gasoline particulate filter EGT sensor Exhaust manifold Muffler Oxygen sensor Cooling system Air cooling Water cooling Electric fan Radiator Thermostat Viscous fan (fan clutch) Lubrication Oil Oil filter Oil pump Sump (wet, dry) Other Knocking / pinging Power band Redline Stratified charge Top dead centre Portal Category --- Adapted from the Wikipedia article [Engine control unit](https://en.wikipedia.org/wiki/Engine_control_unit) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Engine_control_unit?action=history)). 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