Hello and welcome to the forum, the lads on here are very, very helpful and friendly. This is just the place to help you with your Catera. I'm told the V6 Ecotec engines are not popular in North America as relatively small capacity and need lots of love and attention!
This is true! When I picked up the car, I was shocked at how many people hate theirs. Some of the comments I've heard include: The tires wear too quickly because they're "for european roads" (apparently camber is unique to europe) etc. etc.
I bought the car with a blown head gasket as a rebuild project, and I can say it's far from an easy car to work on, but the overall quality is quite good. definitely worth the $800 I paid for it.
I think many people learned to hate these cars because they figure that as a "cadillac" they would be as easy to get parts for and maintain as any other domestic car in North America. Sometimes they can be a bit trickier to get things for, but not any harder than any other imported luxury car.