← Yury Sergeev

CarPi drive log

Engine data from my 2017 Audi A3, requested from the ECU over CAN by a Raspberry Pi on the OBD-II port, about 8 times a second.

Loading drives…

Drives

Signal trace

Hover to read values · drag to zoom · double-click to resetBest explored on a laptop: hover to read, drag to zoom

 

Fuel trim by engine speed

Sensor checks

Every decoded value compared against a physical or expected reference before the data is trusted.

    How it's built

    1. Pi 4 + MCP2515 on the OBD-II port
    2. OBD-II polling over SocketCAN
    3. One CSV per drive
    4. Python analysis in a GitHub Action
    5. This page

    The car's gateway blocks passive listening, so the logger asks the engine for each value, with a small ISO-TP layer for multi-frame replies. Code, hardware notes and the full report are on GitHub.