Check/Clear engine codes. Display/log engine parameters. Dyno your OBDII car for ~$20 if you have an Android BT device

4 things in one:

1) Check engine codes that trip your CEL/SES (Check engine light / Service Engine Soon). FYI this can also be accomplished at places like Autozone for free if you want to spend the time to drive there. You can then google what the codes mean.
2) Clear your CEL/SES light. FYI this can also be accomplished for free by unplugging your battery
3) Display / Log engine diagnostics real time (Temps, load, etc that aren't just displayed on your dash. Your ECU (car computer) is actually monitoring many inputs for optimal output)
4) Display how much horsepower/torque your car is putting to the ground. A dyno run on a machine can easily cost $20+ "per pull"

The OBDII Standard (on board diagnostics) was made mandatory for all cars sold in the US in 1996

So if your car is newer than that and you have an Android BT device this is for you if you want a cheap scan/diagnostic/logging device w/o lugging around your laptop or hooking up to a desktop.

Stuff you need:
1) Buy an ELM327 BT device (they go for ~$15 on ebay)
2) Buy the TORQUE application (~$5) https://market.android.com/detail...owl.torque
3) Optional: If you want to dyno your car on the road for an estimate of your car's power: http://www.bradbarnhill.com/proje...rtualDyno/

Attached bellow is the VirtualDyno #s from my car after I did a couple mods to it, a nice before/after shot to see what it gained.