2003 Cadillac CTS Repair Question
Mileage: 160,000 miles.
Cadillac CTS Engine Problem
Those two things don't have to be related although I suppose something unusual could have happened. With so much detail to sort through there are dozens of possibilities. Some of them depend on which engine you have. Besides that obvious information that you didn't share, you need to supply some hint of the symptoms and observations. I don't have enough time left in my life to type all of the possible causes and fixes.
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