RE: obd2 code reading without tool
to test the ckp sensor, you need to locate the 2 wires comings from it, and using a graphing multimeter, or an analog multimeter, connect the meter to both leads of the ckp sensor. crank the motor and you should get an a\c voltage varying from -1v to +1volt.
You should get a nice consitant sine wave on the graph.
The tools needed to test them can get kind of pricey so most people usually just replace them for less than $50.
Another way of testing them, if to just crank the motor and watch the rpm gauge on the cluster. If your getting a constant rpm of around 100rpm, usually its not that culprit.