After getting the engine light on I do the test ( insert key, turn on, turn off, turn on, turn off, turn on ) and get this error codes:
P0455 / P0456
Can I drive the minivan without any problem.
Do I need to go urgently to the dealer so they fix this problem.
Reading here I found that this problem is related to some hoses broken.
Also the error codes from here ( http://www.allpar.com/fix/computer-codes.html ) say: Evaporative Emission (EVAP) System Leak Detected
Also on other web page they say this:
P0455 AND P0456 are all evaporative leak monitor test failures (medium and large leaks).