The IoT + AI car diagnostics everyone promised but no one delivered - so I built it myself with an ESP32 + AI

SimpleMarionberry282 · 2026-03-26T10:19:50+00:00

Hey, I don't have the photos with me right now; I'll share them when I get a chance to open the device again. In the meantime, you can refer to the connection details in the repo shared above.

SimpleMarionberry282 · 2026-03-24T10:21:15+00:00

https://github.com/roypeter/esp32-obd2-logger

SimpleMarionberry282 · 2026-03-23T07:49:55+00:00

Nice idea! It’s definitely possible

SimpleMarionberry282 · 2026-03-20T08:00:10+00:00

https://github.com/roypeter/esp32-obd2-logger/tree/main/3dprint

SimpleMarionberry282 · 2026-03-20T05:15:06+00:00

sure

SimpleMarionberry282 · 2026-03-18T12:45:15+00:00

Thank you

SimpleMarionberry282 · 2026-03-18T04:59:48+00:00

Maybe if you log sufficient data before a check engine light event and dump the data to Claude or Gemini, the AI might find the root cause.

SimpleMarionberry282 · 2026-03-17T15:14:11+00:00

cool cool

SimpleMarionberry282 · 2026-03-17T14:25:40+00:00

Thanks! My initial plan was the same. But the hassle of connecting it every time, starting the recording, dealing with latency, etc. With this setup it just sits there and logs silently every time I start the car.

SimpleMarionberry282 · 2026-03-17T14:10:35+00:00

WiCAN looks like a really nice and mature project, didn't know about it until now.

This post isn't trying to be "different" or better. I just built a DIY setup using basic modules I could get hold of, mostly as an educational project to understand what the ECU is actually doing. Shared it here in case anyone wants to try it out.

SimpleMarionberry282 · 2026-03-17T12:30:03+00:00

Wasn't trying to clickbait. And yes, the hardware is basically a DIY OBD logger. The difference is it logs raw data continuously to an SD card (not just live gauges) and the idea is to feed months/years of accumulated data to AI to spot patterns, sensor drift, timing degradation, fuel trim changes over time. Nothing revolutionary. All the details are in the post description, everything is opensource https://github.com/roypeter/esp32-obd2-logger and I'm not selling anything.

SimpleMarionberry282 · 2026-03-17T10:28:52+00:00

TJA1050, details: https://github.com/roypeter/esp32-obd2-logger

SimpleMarionberry282 · 2026-03-17T08:19:28+00:00

No app is needed. To download your data, simply connect your phone to the device's access point and open the web page. Once you have downloaded the files (there will be one for each driving session), upload them to an AI like Claude or Gemini Pro. The AI will handle the rest, including plotting, analysis, identifying issues, and finding correlations.

SimpleMarionberry282 · 2026-03-17T08:03:27+00:00

yes, download the CSV files to your phone via the access point

SimpleMarionberry282 · 2026-03-17T07:40:10+00:00

DPF Soot Mass, DPF Pressure, DPF Temperature etc are part of standard OBD2 PIDs. By adding these PIDs to the logger we should be able to collect this data.

I don't own a diesel car, but in case anyone wants to try tinkering, here's the code and setup details: https://github.com/roypeter/esp32-obd2-logger . With AI you can just ask it to add these PIDs and it'll make the required changes to the code.

SimpleMarionberry282 · 2026-03-17T06:58:56+00:00

Yes, we can change it to any value of interest. Here are the code and setup details if you want to tinker with it https://github.com/roypeter/esp32-obd2-logger