This past Saturday after a trip of about 20 miles total and a rest period of 30 minutes I again started out in the XC.  The check engine light came on as soon as I started the engine. I stopped the engine and checked the gas cap as covered in the owner’s manual. Cap was on tight, but gave it a couple of clicks anyway.  I took a look under the hood found all fluid levels fine and did not see any thing that looked like trouble.  I thought it best not to drive the car any more that weekend and take it straight to the local dealer Monday morning. I purchased this car at another dealer and was somewhat nervous about them giving me trouble when I arrived. I drove to the local dealer Monday morning and I was  greeted with enthusiasm by the service. department. They said they would take a look and call me as soon as they determined the cause of  the check engine light.  Service Adviser called about 110 a.m. and said that the cause was a collapsed vacuum house.  He stated that Error message  read out was "no vacuum". He did not know why this had happened and said that perhaps it was installed incorrectly. He stated that he had ordered the hose and it would arrive after lunch and car could be picked up after 4.  When I picked up the car the Service Advisor showed me the replacement hose on the engine. It's located at center of engine and one end  can easily be seen with hood up and looking down at engine.  It is about a 3/4 inch diameter molded hose with a right angle bend on front side of engine and has crimp on clamp.  XC seems fine now. Anyway another data point on Check Engine light.   Tom