Can't say enough positive stuff about getting an OBD2 reader, they're freaking fantastic.
I drive my poor car so freaking hard and I've had a bad misfire when it gets up to temp that no one has been able to diagnose. In less than 24h owning this widget I discovered it was misfiring on all 4 cylinders when it got hot on a low tank of gas. My theory is that the turbo is boiling the gas return line and it's heating up the tank. When the fuel pump goes to work it's not sending enough pressure (because hot gas / insufficient lube in the pump (gas lubes the pump)).
TL;DR epic little widget.