I want to connect my PDA (iPAQ rx3115) to my car (97 Camaro) for the pure purpose of reading a check engine light. Because of this, i think the cord needed will be cheaper, any ideas?

There are places like http://www.auterraweb.com/index.html that do OBD-II PDA stuff (and others-Google for them). I don't think you will come out any cheaper, though. Maybe if you posted in the diagnostics/programming forum...

AutoTap and Auterra have scan software that works with the Palm OS. Not sure what the iPAQ uses though.

Autrrae doesn't offer for Pocket PC, just palm os, sorry.

Autotap is just to damn expensive.

I heard there was a wireless bluetooth out there available as well.