Looking for advice with an OBDuino project.

Hi everyone I hope I chose the right place to put this if not sorry. I’m new to arduino projects but I’d like to make an OBDuino for my car. I had posted a similar thread on ecomodder but most of the people there who developed the project are no longer active.

So I’ve been doing research on the project but one of the biggest problems I’ve been running into is that the build instructions are old and the pictures don’t work anymore. Which is a issue when the post says “it should look like this” but the picture is missing.

So far I’ve come up with this

My car info is:
2002 Pontiac Sunfire SE Sedan
2.2l Ecotec
4 Speed Auto
VPW (J1850) Protocol

Parts List :

I’m looking at LCDs now I want to use a 4x20 size one if it would work.

I’ve been reading about the OBD cable I’m trying to figure out how to make one for my cars protocol right now I’m not sure though if I need an ELM or not. If you can help me out on that I’d really appreciate it.

Please let me know if I should use different parts like I said before this is my first arduino project so I’m doing as much research as I can but I don’t have any experience to know if these are all correct parts.

I have the links to the project that I’ll post below



Source code


Thanks for any help.

I did a bit more looking around and it seems as though there isn't much new info on the OBDuino or any vehicle telemetry projects in the last few years. Has anyone made one of these recently?

I have a question about the OBD II cable if I were to get just the plug like this one https://www.sparkfun.com/products/9911 . Can I wire it directly to the arduino board? Or do you absolutely need an interface like the ELM to get it to work? I'm not really worried about the code at this point I just want to know if it is possible to wire the OBD cable directly to the arduino and still be able to read the data from it.

Can I wire it directly to the arduino board?

You can but you shouldn't because it runs on 12V and that would destroy your Arduino.

Or do you absolutely need an interface like the ELM to get it to work?

No, you can do that interface yourself but a chip like the STN1110 is much easier and way cheaper than doing it yourself.