Engine codes P045.6 and P168.4

Hi,
Looking for description of diagnostic trouble codes (P045.6 and P168.4) for a 2002 Dodge Caravan with 3.3 litre engine. Car seems to run fine so I am guessing emission related. Codes obtained by turning ignition on/off 3/2 times and reading trip meter. Thanks!

Never mind. I found the codes on another forum dedicated to OBDII codes. P0456 is just another code for a small evap leak detected. Not sure why there is more than one code for the same problem, curious but I will get over it. My Haynes manual says to check the hoses so that is what I will do. The gas cap looks okay but if the hoses check out okay I will replace the cap. Nice to know my instinct was right that it was an emission code.

Update: I ordered the gas cap instead of checking the lines. Did not resolve the issue as the trouble code came back. Tonight I took out the Air Filter housing and followed the purge solenoid input hose back to the A/C dryer. There I found a 2 inch long rubber connector hose that was badly cracked. For now I just taped it but will replace soon. If anyone knows what diameter the tube is it will help me get the right size hose. It looks like about 3/8-1/2" in diameter. Thanks.