I turn the key and it just turns over, it is like it is out of gas, but I know for sure it is not. Could the fuel filter be clogged? Thanks for any help.

No, take it to cadillac and they should fix it for free, as long as you have a warranty. I had the same problem and took it toCadillac.Myrepair bill has codes P0335 and P0341 are doing it. You will have to replace Crankshaft and Camshaft Positions Sensors. Its going to cost around $490 with out warranty. Good Luck, Big C

I had similar experience with my 2003 CTS. P0335 & P0337 (Crank Shaft sensor). Mine just died driving down the highway. Waited about 30 minutes and would turn over and then die again.

Replaced sensor - worked ever since. Cost was ~$250

it is the crankshaft sensor, many people have had the same problem around the same time(on 03 models)