I have a 2005 Cadillac CTS that has 98,500 miles on it, and automatic transmission. Don't have a code reader. When I got the car I was told it would run so I put a battery in it but then I had to go help some people with their brakes, took al day. When I got back about 8 maybe 9 hours later the battery was dead. Bought a new battery installed it but was late so I went to bed next day the battery was dead. Been on the caddy forums nobody has a solution. Even the ones that took their cars to the dealer couldn't be fixed according to GM. Have you ever run across this problem it affects more caddys than just the CTS. Is this something like the timing chain mess that GM didn't fix till 2012 which I have to change my timing chains also. I think I heard you mention the timing chain thing that probably where I got it. Anyway any help would be greatly appreciated.