Engine control unit
Anengine control unit(ECU), also called anengine control module(ECM),[1]is a device which controls multiple systems of aninternal combustion enginein a single unit. Systems commonly controlled by an ECU include thefuel injectionandignitionsystems.
The earliest ECUs (used by aircraft engines in the late 1930s) were mechanical-hydraulic units; however, most 21st-century ECUs function bydigital electronics.
Functions[edit]
The main functions of the ECU are typically:
- Fuel injectionsystem
- Ignition system
- Idle speedcontrol (typically either via anidle air control valveor theelectronic throttlesystem)
- Variable valve timingand/orvariable valve liftsystems
The sensors used by the ECU include:[2]
- accelerator pedal position sensor
- camshaftposition sensor
- coolant temperature sensor
- crankshaft position sensor
- knocksensors
- inlet manifoldpressure sensor (MAP sensor)
- intake air temperature
- intake airmass flow ratesensor (MAF sensor)
- oxygen (lambda) sensor
- throttle position sensor
- wheel speed sensor
Secondary[edit]
Other functions include:
- Launch control
- Fuel pressure regulator
- Rev limiter
- Wastegatecontrol andanti-lag
- Theft prevention by blocking ignition, in response to input from animmobiliser
In acamless piston engine(an experimental design not currently used in any production vehicles), the ECU has continuous control of when each of theintake and exhaust valvesare opened and by how much.[3][4]
Early systems[edit]
One of the earliest attempts to use such a unitized and automated device to manage multiple engine control functions simultaneously was the created byBMWin 1939Kommandogerätsystem used by theBMW 80114-cylinderradial enginewhich powered theFocke-Wulf Fw 190 V5fighter aircraft.[5]This device replaced the 6 controls used to initiate hard acceleration with one control, however the system could cause surging and stalling problems.[citation needed]
Usage in motor vehicles[edit]
In the early 1970s, theJapanese electronics industrybegan producingintegrated circuitsandmicrocontrollersused for controlling engines.[6]TheFord EEC(Electronic Engine Control) system, which utilized theToshibaTLCS-12 microprocessor, went into mass production in 1975.[7]
The first Bosch engine management system was theMotronic 1.0,which was introduced in the 1979BMW 7 Series (E23)[8]This system was based on the existingBosch Jetronicfuel injection system, to which control of the ignition system was added.[9]
In 1981, aDelco ElectronicsECU was used by severalChevroletandBuickengines 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]
Usage in aircraft engines[edit]
Such systems are used for many internal combustion engines in other applications. In aeronautical applications, the systems are known as "FADECs"(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 acarburetedengine with amagneto ignitionsystem that does not require electrical power generated by analternatorto run, which is considered a safety advantage.[12]
See also[edit]
- Air-fuel ratio meter
- Check engine light
- List of auto parts
- On-board diagnostics(OBD)
- Powertrain control module(PCM)
References[edit]
- ^"How an Automotive Computer Works".2carpros.Retrieved14 May2023.
- ^"Toyota Prius - Engine Control Systems"(PDF).autoshop101.Retrieved14 May2023.
- ^Austen, Ian (2003-08-21)."WHAT'S NEXT; A Chip-Based Challenge to a Car's Spinning Camshaft".The New York Times.Retrieved2009-01-16.
- ^"How Proportional Valve Control Module control the oil flow direction".genndih.Retrieved2023-06-03.
- ^Gunston, Bill (1989).World Encyclopedia of Aero Engines.Cambridge, England: Patrick Stephens Limited. p. 26.ISBN978-1-85260-163-8.
- ^"Trends in the Semiconductor Industry: 1970s".Semiconductor History Museum of Japan.Retrieved27 June2019.
- ^"1973: 12-bit engine-control microprocessor (Toshiba)"(PDF).Semiconductor History Museum of Japan.Retrieved27 June2019.
- ^"25 years of Bosch Motronic: Think tank under the bonnet".bosch.Archived fromthe originalon 23 June 2006.
- ^Probst, C. (27 November 1989).Bosch Fuel Injection and Engine Management.Robert Bentley, Incorporated.ISBN978-0-8376-0300-1.Retrieved13 May2023.
- ^"GM Emission Control Project Center - I Was There".gmheritagecenter.Archived fromthe originalon 3 July 2017.
- ^Delco Electronics Electron Magazine, The Atwood Legacy, Spring '89, page 25
- ^Pilot's Encyclopedia of Aeronautical Knowledge.Federal Aviation Administration.