Just purchased only has 65,000 miles beautiful car but sometimes runs very rough at idle and will drive just as rough. Other times it runs smooth as glass. I checked the codes got lots of history codes and one active code. This is my first Cadillac and the mechanics around here are parts changers i need help to get this beautiful car running right

History codes:
Po23
Po52
Po53
Po57 only current code****
Po91
Po95
P109
So16
So44
So55
So61
So62

I'm lost and don't want to change a bunch of unneeded parts. From what I understand the car sat for 2 years after it was inherited from the original owner to his grandson.

Any help would be greatly appreciated

 

I am sure this would be a beauty because this model is certainly amazing. I am sure that your enjoying your rides and that's the most important part of it which can be taken to the next level.