I recently bought a 02 ZX5 w/58k miles and a 2.0 ztech it runs and drives fine but it feels like it is down on power. I live in the upper ohio valley and we have some hills and at 65mph with the cruse set it will back shift to 4000rpms to make the hills, and some of them are not that big. Is it just me or is this normal for this little motor. I bought the car for my daughter so im not looking to make big power I just dont want somthing to be wrong and cost big bucks.