Fuelie is a Mac & Windows desktop app that helps you analyze data logged from your car's ECU. It's currently focused on helping you analyze logged air-fuel ratios from your wideband oxygen sensors.
It works with data from any car or ECU provided you can get the logged data out in CSV or TSV format. See the configuration section for details on setting it up for your ECU.
Set up your target AFR
And it will offer percentage change suggestions:
You can even configure the math behind the suggestion.
Play back your logfile:
Playback UI features
arrows:- When grid is selected: move selection
- When grid is not selected:
left&rightscrub playback by one sample
shift+left|right: scrub playback by 10 samplesspacebar: play / pause from current locationcmd+option+left|right(ctrl+option+left|rightWindows): move between tabscmd+c(ctrl+cWindows) in the grid: copy selected cellscmd+v(ctrl+vWindows) in the grid: paste selected cells (pasting/editing only available in target AFR)cmd+,(ctrl+,Windows): open your configuration file
Before you open a log file, you will probably need to configure the app to work with your setup.
At this time, you set the app up for your car / ECU by editing a JSON config file. Open the app then open the file with cmd+, or ctrl+,
Note: Check out a JSON cheat sheet for formatting rules. JSON is very strict: double quotes only, no stray commas, etc. If you see a not-very-descriptive error in the config editor, it's probably a JSON formatting problem. The JSON editor within the app attempts to paper over some of this (adding / converting quotes, removing trailing commas), but can't read your mind.
{
// Matches the profile.name from the list of profiles
"currentProfile": "Default",
"profiles": [
{
"name": "Default",
// The fuel map headers will be used to locate which cells are accessed in
// your fuel table.
"fuelMap": {
// Row headers
"rows": [9, 6, 3, 1, -0, -1, -2, -3, -4, -5, -6, -8, -9, -10, -11, -12, -13],
// Column headers
"columns": [ 500, 1000, 1500, 2000, 2500, 3000, 3500, 4000, 4500, 5000, 5500, 6000, 6550, 7000, 7500, 8000, 8500, 9000, 9500, 10000, 10500]
},
"units": {
"mixture": "afr",
"temp": "f",
"speed": "mph",
"manifoldPressure": "psi",
"manifoldPressure": "psi",
},
// Set up how the app should read your logfile
"logFile": {
// Currently time should be decimal seconds starting from 0
"time": "Time/s",
// Table row will be interpolated based on the row headers and the CSV
// column specified here
"row": "Engine Load",
// Table column will be interpolated based on the column headers and the
// CSV column specified here
"column": "Engine Speed",
// Specify one or more oxygen sensor columns
"mixture": ["O2 #1"],
// Parse values as this by default. float is recommended
"defaultType": "float",
// (optional) Set up specific columns for correct display in the sidebar
"columns": {
"Engine Speed": {
"type": "integer" // types can be "integer", "float", or "string"
},
"Coolant Temp": {
"type": "integer"
}
"Fuel Pulse": {
"decimals": 2
},
"Dont Care": {
"visible": false,
"comment": "Not visible cause it is a dupe..."
},
"ADCR03": {
"name": "Oil Press (psi)",
"decimals": 1,
"valueFormula": {
"result": "value * 37.5 - 18.75"
}
},
"ADCR01": {
"name": "Oil Temp (F)",
"type": "integer" // the type displayed
"rawType": "float", // the type that feeds into value transform
"valueTable": [
[ 0.47, 290 ],
[ 0.86, 240 ],
[ 1.39, 200 ],
[ 2.42, 150 ],
[ 3.64, 100 ],
[ 4.52, 50 ],
[ 4.88, 0 ]
]
}
},
// (optional) Specify the order to display log columns in the sidebar on
// playback. Any columns not specified in this list will be displayed
// after the specified columns in their original order.
"columnDisplayOrder": [
"Time/s",
"Engine Load",
"Engine Speed",
"Throttle",
"Vehicle Speed",
"O2 #1",
"O2 #2"
]
},
// Settings for the average fuel mixture table(s)
"avgFuelMixture": {
// Values outside this range will be ignored
"minValue": 7,
"maxValue": 20,
// A log line must cross this cell weight threshhold to be included in
// the average. Range 0 to 1.
// When a row and column are calculated from the engine load & speed, a
// single cell is almost never used by the ECU. It uses a blend
// (interpolation) of 4 cells. The higher the value, the more a log
// sample is affecting this cell.
"minWeight": 0.2,
// The aggregate weights of all samples in this cell must be over this
// threshhold to be included in the average table.
"minTotalWeight": 1,
// (optional) ignore rows that meet some condition. You can access any
// column in the log file
"ignore": [{
"accel": "Fuel Trim (Accel)",
"condition": "accel > 600"
}]
},
// Settings for suggested changes
"suggestedMixtureChange": {
// units are used for display only at this time
"units": "%",
// Expression to calculate the suggested value for a single cell. This
// expression has several variables available to it:
//
// * `loggedValue` - The average mixture value in the cell
// * `targetValue` - The target mixture value in the cell
// * `rowIndex` - The cell's row index
// * `colIndex` - The cell's column index
// * `avgFuelMixtureTable` - The entire table. Access cells via
// avgFuelMixtureTable[rowIndex][colIndex]. Each cell has a number
// of properties:
// * `value` - same as loggedValue
// * `rawValue` - full precision value
// * `min` - min mixture value sample
// * `max` - max mixture value sample
// * `length` - total samples
// * `weight` - total weight
"suggestedValue": {
"result": "(loggedValue / targetValue - 1) * 100"
}
},
// Settings for mixture difference table. Used when there is more than one
// O2 sensor reading in the log file.
"mixtureDifference": {
// units are used for display only at this time
"units": "",
// Expression to calculate the difference in a single cell. Available
// variables:
//
// * `mixture0` - First O2 sensor average mixture value in the cell
// * `mixture1` - Second O2 sensor average mixture value in the cell
// * `targetValue` - The target mixture value in the cell
// * `rowIndex` - The cell's row index
// * `colIndex` - The cell's column index
// * `avgFuelMixtureTable0` - First O2 sensor's entire table
// * `avgFuelMixtureTable1` - Second O2 sensor's entire table
"difference": {
"result": "mixture1 - mixture0"
}
}
// Edit this in the app's target tab
"fuelMixtureTarget": {
"table": []
},
"charting": {
"zoom": {
"pointsInView": 1200,
"maxPointsInView": 6000
},
"scales": {
},
"pages": [
{
"name": "Custom Charts",
"charts": [
{
"lines": [{
"column": "O2 #1",
"color": "red",
}, {
"column": "O2 #1",
"color": "green",
}]
},
{
"lines": [{
"column": "Air Temp",
"color": "pink",
}, {
"column": "Coolant Temp",
"color": "blue",
}]
}
]
}
] // end tabs
}
}
]
}- Per-window profile selection
- Make default target afr better
- Cmd-z undo
- Can take files as parameters (open with ...)
If you don't have it already, install nvm (or nvm-windows). Then install node and yarn:
nvm install 14.15
nvm use 14.15 # make sure you're on node 14.x
npm install --global yarnThen get the app running
yarn install
yarn dev # starts the appOnce running, you can make changes and they should immediately be reflected in the running app.
MIT License