For me the Range Sensor was the worst always went bad 3 weeks to a month everytime it was either in the shop or in my driveway not drivable its a good car when its on the road but that was barely the case
Motor installed July 2013 w/ 43,000 miles. Now has less than 79,000 on replaced motor. Have documentation with receipts showing $3,000 in replacement costs of motor, timing belt, radiator, etc. (fan belt broke & mom in law ruined motor but loved car so much we replaced it). Replaced tires 9/16 and repaired AC. Very clean car, very good interior, very good paint, very good air conditioning, glitchy radio but sound system phenomenal w cd player, mp3 or cassette. I plan replace K134 to fix radio sound
After my wife totalled my Chrysler 300, she bought a 2001 Catera from our mechanic. The sold it to us for $600 + $2,400 in repairs. It seemed OK at first. I suppose I shoudn't have let her buy such an old car. The water pump went, then the fuel pump, then the key lock. As stated by others, the sunroof has a mind of its own. I am spending, on average, about $600 / month to keep this thing on the road. It still needs from front end work. They don't make the part for the electronic anti-theft key anymore; mechanic had to order the part from MO. I have put my wife to task to do something about this thing. We have to get rid of it. Getting rid of it was one of the six happiest days of my life. They don't call it a Cadillac Caterrible for nothing. I dumped it.
It is a good car. People never change timing belts, check oil and antifreeze and then complain about engine failure. Some other problems, which were solved are very common for other cars: ignition coils die all the time on Fords and Nissans, valve cover gaskets need to be replaced on Toyotas. All reliability problems were solved by GM by 2000. 2000 and 2001 are reliable cars.
My very first car turned out to be a lemon and a stressor on my mother. Seemed like a nice, clean car that wouldn't cost me a lot because it was a Cadillac and Cadillac's usually are pretty dependable. But this car, just was an EPIC FAIL. Now I'm trading it in and getting this burden off of me and my mother! Engine repair costed $2000, then the brakes, then tires, then transmission (which has to be injected into engine which is even more money) sunroof works when it wants to, back wheel drive stinks (especially in snow and ice), power locks on driver side went out, and on top of all of that, CRAPPY gas mileage...please don't ever buy this car...all of these cars should be set on fire!!
Comfortable, leather, heated seats.
Fun to drive.
If they decided to bring this car back for the 2012 year (which I doubt, just giving a scenario), they have a lot of improvements ahead of them.