1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Glossary for Abbreviations\Technical Documentation

Discussion in 'General Discussion' started by JoeJack88, Feb 6, 2007.

  1. JoeJack88

    JoeJack88 Well-Known Member Super Moderator Donated!

    A/C = Air Conditioning
    A/F = Air/Fuel Ratio
    A/T = Automatic Transmission or Transaxle
    ABS = Antilock Braking System
    ABSV = Air Bypass Solenoid Valve
    AC = Alternating Current
    ACTS = Air Charge Temperature Sensor
    AFC = Air Flow Control
    AFM = Air Flow Meter
    AFS = Air Flow Sensor
    ALCL = Assembly Line Communications Link
    ALDL = Assembly Line Data Link
    APS = Absolute Pressure Sensor
    APS = Atmospheric Pressure Sensor
    ASDM = Airbag System Diagnostic Module
    ATA = Air To Air
    ATAIC = Air To Air InterCooler
    ATDC = After Top Dead Centre
    ATF = Automatic Transmission Fluid
    ATS = Air Temperature Sensor
    AWD = All Wheel Drive
    B+ = Battery Positive Voltage
    BARO = Barometric Pressure
    BAT = Battery
    BCM = Body Control Module
    BHP = Brake Horse Power
    BMAP = Barometric/Manifold Absolute Pressure Sensor
    BPS = Back pressure Sensor
    BPT = Back Pressure Transducer
    BTDC = Before Top Dead Center
    Btu = British Thermal Units
    C = Celsius
    C3I = Computer Controlled Coil Ignition
    CALPAK = Calibration Pack
    CAN = Controller Area Network
    CANP = Canister Purge Solenoid Valve
    CAS = Crank Angle Sensor
    CC = Cubic Centimetres
    CDI = Capacitor Discharge Ignition
    CEAB = Cold Engine Air Bleed
    CECU = Central Electronic Control Unit
    CER = Cold Enrichment Rod
    CESS = Cold Engine Sensor Switch
    CFI = Central Fuel Injection
    CFI = Continuous Fuel Injection
    cfm = Cubic Feet Per Minute
    CID = cylinder identification sensor
    CID = Cubic Inch Displacement
    CIS = Continuous Injection System
    CKP = Crankshaft Position Sensor
    CMP = Camshaft Position Sensor
    CO = Carbon Monoxide
    CO2 = Carbon Dioxide
    COP = Coil On Plug ignition
    CPI = Central Port Injection
    CPU = Central Processing Unit
    CSSA = Cold Start Spark Advance
    CSSH = Cold Start Spark Hold
    CTS = Coolant Temperature Sensor
    CTVS = Choke Thermal Vacuum Switch
    CVR = Control Vacuum Regulator
    dB = Decibels
    DC = Direct Current
    DEFI = Digital Electronic Fuel Injection
    DFS = Deceleration Fuel Shutoff
    DIS = Distributorless Ignition System
    DIS = Direct Ignition System
    DLC = Data Link Connector
    DOHC = Double OverHead Camshaft
    DPF = Diesel Particulate Filter
    DTC = Diagnostic Trouble Code
    DVOM = Digital Volt Ohm Meter
    E2PROM = Electrically Erasable Programmable Read Only Memory
    EACV = Electronic Air Control Valve
    EBCM = Electronic Brake Control Module
    EBC = Electronic Boost Controller
    EBM = Electronic Body Module
    ECA = Electronic Control Assembly
    ECM = Engine Control Module
    ECT = Engine Coolant Temperature
    ECU = Electronic Control Unit
    EDIS = Electronic Distributorless Ignition System
    EEPROM = Electronically Erasable Programmable Read Only Memory
    E2PROM = Electronically Erasable Programmable Read Only Memory
    EFC = Electronic Fuel Control
    EFCA = Electronic Fuel Control Assembly
    EFI = Electronic Fuel Injection
    EGO = Exhaust Gas Oxygen Sensor
    EGR = Exhaust Gas Recirculation
    EGRPS = EGR Valve Position Sensor
    EGRT = EGR Temperature
    EGT = Exhaust Gas Temperature
    EI = Electronic Ignition
    EMI = Electromagnetic Interference
    EMR = Electronic Module Retard
    EOS = Exhaust Oxygen Sensor
    EOBD = European Onboard Diagnostics
    EPOS = EGR Valve Position Sensor
    EPROM = Erasable Programmable Read Only Memory (chip)
    ESC = Electronic Spark Control
    EST = Electronic Spark Timing
    EVAP = Evaporative Emission System
    EVP = EGR Valve Position
    F = Fahrenheit
    FBC = Feedback Carburetor System
    FBCA = Feedback Carburetor Actuator
    FCS = Fuel Control Solenoid
    FDC = Fuel Deceleration Valve
    FI = Fuel Injection
    FIPG = Form In Place Gasket
    FLS = Fluid Level Sensor
    FMIC = Front Mount InterCooler
    ft.lb. = Foot Pound
    FWD = Front-Wheel Drive
    GAL = Gallon
    GDI = Gasoline Direct Injection
    GEN = Generator
    GND = Ground
    GPM = Grams Per Mile
    GPS = Global Positioning System
    GVW = Gross Vehicle Weight
    H20 = Water
    HC = Hydrocarbon
    HEGO = Heated Exhaust Gas Oxygen Sensor
    HEI = High Energy Ignition
    Hg = Mercury
    HO2S = Heated Oxygen Sensor
    hp = Horsepower
    HT = High Tension
    IAC = Idle Air Control
    IAT = Intake Air Temperature
    IATS = Intake Air Temperature Sensor
    IC = Integrated Circuit
    ICM = Ignition Control Module
    ICS = Idle Control Solenoid
    ID = Inside Diameter
    IFI = Indirect Fuel Injection
    IGN = Ignition
    ISC = Idle Speed Control
    ISO = International Standards Organization
    ITCS = Ignition Timing Control System
    ITS = Idle Tracking Switch
    JAS = Jet Air System
    JDM = Japanese Domestic Market
    kHz = Kilohertz
    Km = Kilometres
    KOEC = "Key On, Engine Cranking"
    KOEO = "Key On, Engine Off"
    KOER = "Key On, Engine Running"
    kPa = Kilopascals
    KS = Knock Sensor
    KV = Kilovolts
    L = Litres
    lb. ft. = Pound Feet
    LCD = Liquid Crystal Display
    LED = Light Emitting Diode
    LHD = Left-Hand Drive
    LTFT = Long Term Fuel Trim
    LWB = Long Wheel-Base
    MAF = Mass Air Flow
    MAP = Manifold Absolute Pressure
    MAT = Manifold Air Temperature
    MBC = Manual Boost Controller
    MCS = Mixture Control Solenoid
    MCT = Manifold Charge Temperature
    MFI = Multi Port Fuel Injection
    MIL = Malfunction Indicator Light
    mm = Millimetres
    MPFI = Multi Point Fuel Injection
    MPG = Miles Per Gallon
    MPH = Miles Per Hour
    MPI = Multi Port Injection
    MPV = Multi-Purpose Vehicle
    ms = Millisecond
    mV = Millivolts
    Nm = Newton Metres
    NOX = Oxides of Nitrogen
    NVRAM = Nonvolatile Random Access Memory
    O2 = Oxygen
    O2S = Oxygen Sensor
    OBD = Onboard Diagnostics
    OBD I = Onboard Diagnostics One
    OBD II = Onboard Diagnostics Two
    OD = Outside Diameter
    OE = Original Equipment
    OEM = Original Equipment Manufacturer
    OHC = OverHead Camshaft
    OHV = OverHead Valve
    OS = Oxygen Sensor
    P/B = Power Bakes
    P/N = Part Number
    PA = Pressure Air
    PAIR = Pulsed Secondary Air Injection
    PAS = Power-Assisted Steering
    PCM = Powertrain Control Module
    PCV = Positive Crankcase Ventilation
    PECV = Power Enrichment Control Valve
    PFI = Port Fuel Injection
    PID = Parameter ID
    PIP = Profile ignition pickup
    PNP = Park/Neutral Switch
    PPM = Parts Per Million
    PROM = Program Read Only Memory (chip)
    PS = Power Steering
    PSI = Pounds Per Square Inch
    PSP = Power Steering Pressure
    pt. = Pint
    PTC = Pending Trouble Code
    PTC = Positive temperature coefficient Additional : This is applied to the way the resistance of a thermistor varies with temperature. In this case, the resistance will increase as the temperature raises
    PWR = Power to Weight Ratio
    RAM = Random Access Memory
    RFI = Radio Frequency Interference
    RHD = Right-Hand Drive
    ROM = Read Only Memory
    RON = Rated Octane Number
    RPM = Revolutions Per Minute
    RWD = Rear-Wheel Drive
    SC = Supercharged
    SEFI = Sequential Electronic Fuel Injection
    SES = Service Engine Soon (light)
    SFI = Sequential Fuel Injection
    SIPS = Side Impact Protection System
    SOHC = Single Over Head Camshaft
    SRS = Secondary Restraint System
    SRS = Supplemental Restraint System (air bag)
    SRT = System Readiness Test
    SS = Speed Sensor
    SSI = Solid State Ignition
    SST = Special Service Tool
    SSM = Special Service Material
    STFT = Short Term Fuel Trim
    SWB = Short Wheel-Base
    TACH = Tachometer
    TB = Throttle Body
    TBI = Throttle Body Injection
    TC = Turbocharged
    TCC = Torque Converter Clutch
    TCM = Transmission or Transaxle Control Module
    TCS = Traction control solenoid (SAAB 9000)
    TD = Turbo Diesel
    TDC = Top Dead Center
    TDI = Turbo Direct Injection (A turbo charged direct injected diesel engine)
    TIV = Thermactor Idle Vacuum Valve
    TKS = Throttle Kicker Solenoid
    TMIC = Top Mount InterCooler
    TPI = Tuned Port Injection
    TPP = Throttle Position Potentiometer
    TPS = Throttle Position Sensor
    TPT = Throttle Position Transducer
    TRD = Toyota Racing Developement
    TSP = Throttle Solenoid Positioner
    TV = Throttle Valve
    TVS = Thermal Vacuum Switch
    TVIS = Toyota Variable Induction System
    TWC = Three Way Catalyst
    TWC+OC = Three Way + Oxidation Catalytic ConverterV V C = Variable Valve Control
    V V T = Variable Valve Timing
    VVTi = Variable Valve Technology with Intelligence
    VSV = Vacuum Switching Valve
    WOT = Wide Open Throttle
    WTA = Water To Air
    WTAIC = Water To Air InterCooler

    Decoding your engine
    first number and second or third letter is the series of block. 2S 3S 5S 1ZZ 2ZZ
    following that will be a dash which begins head and options
    these will all be letters. the first of which will be the head design.
    F heads are for effeciency and made by toyota, G heads are all made by yamaha and built for power. 2S-F 3S-F 3S-G 5S-F 1ZZ-F 2ZZ-G
    the last letter defines the fuel delivery method. for all of us this is an E.
    If you have another letter in the middle it defines air delivery. Z are for superchargers, T are for turbochargers. 4A-GZE 3S-GTE 2JZ-GTE 7M-GTE
  2. JoeJack88

    JoeJack88 Well-Known Member Super Moderator Donated!

    Originally posted by White87GT from 4gcelica.net

    The turbocharger is a centrifugal compressor driven by the otherwise-wasted energy in the exhaust stream. It is a 2 chambered housing with a shaft through the center extending into both chambers. A turbine wheel is mounted on one end of the shaft and is in the exhaust stream, and an impeller wheel is mounted on the other end. That is the compressor end, and it is connected to tubing that goes to the intercooler, and then to the throttle body. A turbocharger is really a very simple device, and as long is it regularly fed clean , high quality oil from the engine lube system, and allowed to cool down before engine shutdown, will last nearly as long the engine itself.

    There are two alternate paths for the exhaust flow at the turbo. One is across the turbine, and the other is out the wastegate, allowing it to bypass the turbo. Since more energy at the turbo means more air to the engine, which means more energy to the turbo, which in turn means more air to the engine, which means...well, I think you get the point. The wastegate is necessary to limit the airflow output from the turbo.
    The wastegate isn't simply open or closed; it modulates to maintain very precise control over the turbo's speed and output.

    Compressors are pumps, and pumps create flow. When the turbo creates more airflow than the engine is consuming, then the air becomes pressurized. So boost pressure will rise and fall as the turbo output increases and decreases. Thats why the wastegte controls the speed and airflow of the turbo. And pressure and flow are directly related. That means you can not get "more flow at the same pressure..."

    The wastegate actuator is simply a can with a rubber diaphragm on one end, and 2 ports with hose fittings on the front end. Looking into the engine compartment form the driver's side, it can easily be seen just to the right of the turbo compressor inlet. The hose on the left is connected to the turbo, and the hose on the right is connected to the T/VSV. (more on that later) There is a spring that holds the diaphragm in place that has a yeild value of about 7 psi.. As pressure builds in the turbo, air begins to fill the actuator and pushes against the diaphragm. When the pressure exceeds the spring value, ~ 7 psi, the actuator moves out, pushing a rod, and opening the wastegate.

    (Turbocharger Vacuum Switching Valve) is a "factory-installed boost controller". It is simply a solenoid-operated valve that, when energized (open) allows air to escape from the actuator, lowering the pressure in the actuator, and allowing the wastegate to modulate closed. This vented air actually flows back into the intake airstream between the airflow meter and the turbo intake so it does not distort the ECU's air/fuel ratio calculations.

    The T/VSV is a normally closed-energized open valve. The ECU will energize (open) it whenever you boost IF 1) engine coolant temps are up to normal , and 2) ambient (intake) air temps are above ~ 32 deg F. (There may be some variation with that number). If the T/VSV is open (high boost mode) and the ECU gets a signal from the knock sensor, it will de-energize (close) the T/VSV. Likewise, if there is an over boost signal from the boost pressure sensor, it will de-energize the T/VSV as part of the "fuel-cut" sequence.

    NOTE: Unless you have an aftermarket boost controller, disabling the T/VSV will lock you into low-boost mode!! It WILL NOT increase boost.

    The normal range of max boost ranges from 7.1 to 11.8 psi, according to the Factory Repair Manual. Low boost problems are almost always a result of some problem in the boost control system and rarely with the turbo itself..

    The boost pressure sensor is simply a pressure transducer that monitors manifold pressure and reports it to the ECU as a voltage value. If the voltage exceeds about 4.4 volts (~12 psi on '91, 92' and early 93's, ~16 psi on late 93's and up) the ECU initiates the fuel-cut sequence. It de-energizes the T/VSV to lower boost, retards ignition timing, and restricts fuel delivery by limiting the injector cycle. The "check-engine" light will come on for about 20 seconds, and a code 34 will be stored in the diagnostic memory. You will be in "limp mode" and unable to boost again until you shut off the engine and restart it. No other reset is required to return to normal operation. You do not have to pull any fuses or disconnect the battery (Internet legend!)

    For a complete schematic diagram of the turbo and boost control system, go here:

    Click on "Boost Control"

    Since the rate and amount of airflow to the wastegate actuator control's its operation, we can increase the boost by either restricting the airflow into the actuator chamber, or by increasing the bleed rate of the air escaping the actuator. Boost controllers range from simple orfice plugs inserted into the hose connecting the turbo the the actuator, to complex multi-valve electronically operated devices, but again, the all do the same thing: they manipulate the amount of air (pressure) in the actuator.

    Since the FC response is programmed in at ~ 12 psi*, you must somehow eliminate it or alter it to boost above ~12 psi. Fuel-cut is initiated when there is a 4.4 volt signal to the ECU from the sensor, so ALL fuel cut defeat (FCD) system either prevent that from happening, or delay it . Some methods simply eliminate FC completely by preventing any thing over 4.3 volts from ever reaching the ECU. This includes the Greddy BCC, the Zener diode, disconnecting the hose, etc. The HKS FCD is an adjustable FCD that has one setting that raises fuel cut to ~17 psi without eliminating it.

    *(late 93's and later have FC set at ~ 16psi from the factory)

    Here is some further information about the HKS FCD (this one is installed on an MR2):


    Or a member from the MR2 Board named BillWOT has designed a simple, fully adjustable FCD that allows you to set FC at any value you want, from stock up to the system max of ~ 17.5. It will cost about $8 for parts and should take less than an hour to build and install. No, I won't build you one.

    Here is a discussion and instructions for the $8 BlackBox FCD:
    *note that installation is on an MR2 and you will have to modify the instructions to fit the location of the ECU on a Celica Alltrac or your Hybrid Swap Celica*


    Car manufacturers measure airflow into an engine with sensors. It lets the ECU make a decision for the air/fuel ratio. The 3SGTE has what is called an AFM or Air Flow Meter. It is a silver box type chamber attached inline on the intake tube.

    Another type of sensor to measure air intake in an engine. The MAP or Manifold Absolute Pressure sensor measures air pressures in the intake manifold, letting the computer make a decision for the air/fuel ratio. The 3SGTE is strange in that it has an AFM and a MAP sensor (however on the 3SGTE the MAP isnt called MAP, its called the Turbo Pressure Sensor). On the 3SGTE the MAP sensor is used to measure positive turbo pressure in the intake manifold. It serves 2 purposes. It gives a reading to the factory boost gauge, and it sends a reading to the ECU. As described above, the ECU will initiate Fuel Cut if boost exceeds the preprogrammed values. This MAP sensor sends those values to the ECU to make that decision. On a 5SFE or other engine, the MAP serves exactly the same purpose as the AFM on the 3SGTE.

    TVIS or Toyota Variable Induction System is a system installed between the intake manifold and the head. It consists of a metal plate that has vacuum operated metal butterflies on it. Below 4500 RPM it is designed to keep the butterfiles in the path of the air entering the head. What it does is increase backpressure in the system, effectively raising low end torque. Above 4500 RPM, a vacuum signal tells the plates to move to the side where they are no longer obstructing flow, thus letting the engine breathe like it needs to at high RPMs. Its an effective way to make high range HP and low end Torque. After 300 or so HP it becomes restrictive, even at high RPM, and is usually in the best interest of the enthusiast to remove.

    I give props to BillWOT because I stole the majority of this FAQ from him off the MR2 board. The information contained within is beneficial to the Celica community and he worded it in such a way to make it very understandable so I changed only what needed to be changed to make the words apply to a celica too. Thanks to Bill. And thanks to everyone else who reads this.

    Posted at Celica.net by Luni
  3. JoeJack88

    JoeJack88 Well-Known Member Super Moderator Donated!

    Water injection explained

    This was posted by a guy on the MR2 board who works with Aquamist Water Injection. Good info

    In brief: Water injection cools the intake charge through the latent heat absorption of water in the evaporation process. Same principal as patio misters. The water vapor absorbs the heat in the intake charge and cools it down. I have seen 30-40 degree Celsius drops on my Power FC monitoring intake temps after the huge air/air intercooler has already done its job.

    Since we know the engine is a giant air pump, and the amount of power it is capable of producing is direction proportional to he volume of cool dense air it is able to ingest, the technology behind water injection makes perfect sense. Think of it this way -- everyone is concerned about air volume:

    "How big of a turbo should I run for my power goals?â€
  4. JoeJack88

    JoeJack88 Well-Known Member Super Moderator Donated!

    AFM voltage-5volts
  5. Stig

    Stig ST162 Guru Donated!

    As we're on the subject, I'd like to list the Toyota acronyns as I'm
    tired of looking stuff up and I'm sure others are too

    Feel free to fill in/add to the list!

    ABS = Anti-lock Brake System
    ADM = Australian Dealer Market
    AFM = Air Flow Meter
    AllTrack = NADM GT4 Model (with Bodykit minus Viscous Diff)
    BGB = Big Green Book
    BVSV = Bimetal Vacuum Sensor Valve
    CASA = Centre Airbag Sensor Assembly (ST182-)
    CCS = Cruise Control System
    ECT = Electronically Controlled Transmission (2 Mode Auto)
    ECT-S = Electronically Controlled Transmission - Sport (3 Mode Auto - JDM only?)
    ECU = Electronic Control Unit (Engine controller)
    EFI = Electronic Fuel Injection
    EGR = Exhaust Gas Recirculation
    EGT = Exhaust gas temp sensor
    EPC = Electronic Parts Catalog
    ESC = Electronic Skid Control (ABS)
    EVAP = Evaporative Emission Control (Charcoal filter sys)
    FPD = Fuel Pulsation Damper
    GT4 = JDM AllTrack Version (No bodykit, Viscous Diff optional)
    ISC = Idle Speed control valve (Inside T/B)
    JDM = Japanese Dealer Market
    LASRE = Lightweight Advanced Super Response Engine
    Live Sound = Fujitsu Speaker System
    NADM = North American Dealer Market
    PCV = Positive Crankcase Ventilation
    PDLS = Power Door Lock System
    PEGASUS = Precision Engineered Geometrically Advanced Suspension
    SRS = Supplemental Restraint System
    TCCS= Toyota Computer Controlled System (includes ECU)
    TSCC = Twin Swirl Combustion Chamber (3S-FE)
    TEMS = Toyota Electronic Modulated Suspension (JDM only?)
    TPS = Throttle Position Sensor
    T-VIS = Toyota Variable Inlet System
    TWC = Three Way Catalyst
    VSS = Vehicle Speed Sensor (inside Speedo)
    VSV = Vacuum Switching Valve

Share This Page