I'm Rick Dill, a new member to USMB, but not new to cars,websites and email lists. I co-ran the Porsche 356 list for more than a decade.
What got me here was dealing with warning lights and the ODB codes behind them. Fortunately a new code reader from Harbor Freight quickly helped me, quicklinking Engine, ABS, and flashing cruise lights to an incident of misfire on a cold damp night with the engine at moderate revs and full throttle. That is ideal for spark failure and identified the problem with a plug in cylinder 4. The good news was that the plug had been mostly working. Four new plugs and the lights all went off.
This seemed good since the shop couldn't even diagnose until next week (holiday and all that) and they suggested it would take two hours to diagnose. OK, it took me four hours total time including the run for plugs and the total cost (mostly scanner) was a little over a hundred dollars.
I've been driving and usually working on cars for over 60 years, but you have to evolve with technology. The information in the OBD scan can be pretty remarkable, sometimes telling things you don't want to hear.