EVAP control unit -- what is it?

I have a P0442 code which is a small leak in the EVAP control unit system. What is the EVAP control unit system? I need to know this to look for the leak!

I believe the code is referring to a problem with the charcoal cannister, purge valve, solenoid or more likely one of the connecting vacuum or vapor hoses.

Check for a loose gas cap. You'll probably need a scanner of some sort to clear the code unless you want to wait until you start the vehicle about 80 times.

Check for a loose gas cap. You'll probably need a scanner of some sort to clear the code unless you want to wait until you start the vehicle about 80 times.

You know, about a month ago, I forgot to put my gas cap back on after refueling one day. Could that have caused the code? How long should it take to clear?

It will definitely cause a code. Don't know exactly how long it will take to clear it. Go to Autozone if you have one and ask them to check your codes and clear them. It's free.

If you look under the hood on the right side facing yur Jeep, there is a rectangular box on it's side with hoses. This is the cannister. Check the hoses. They crack easily. Any crack will allow gas to leak and cause your light.