Cadillac Repair Questions? Ask a Mechanic for Answers ASAP
Hello, my name is ***** ***** I am a professional here at Just Answer. I have noticed that your question was not getting a response and thought I would see if you still need help with this.I apologize for the delay and I hope I can still assist you with this here.Cadillac has released a service bulletin that deals with the type of detonation noise you are describing and the steps to check it. I have enclosed the bulletin in the link below. Copy and paste the link to your browser to open and view it.https://dl.dropboxusercontent.com/u/104923897/Detonation%20Jan%2017.pdf
If you remove the belt and run it for a few minutes dose the noise clear?