So, I learned something new today. My check engine light has been coming on periodically. I found out that if you cycle the key (turn to accessory mode) two times quickly, then the third time leave it on, an error code will pop up. This code will tell you what the problem is. I checked out this site http://www.getahelmet.com/jeeps/tech/codes/
and it told me what my "P0123" code meant.
P0123 (M) Accelerator Position Sensor (APPS) Signal Voltage Too High APPS voltage input above the maximum acceptable voltage.
Now, what does that REALLY mean and how do I fix it?