My stabiliTrak will not turn off. How much is a spark plug sleeve for engine.

What is your question?

My car is running rough. It can pick up speed but I was told that I need to replace the whole engine because the number 2 engine spark plug is out. Would a sleeve in that spot do the trick and help it run better and turn the StabiliTrak off?

What makes this problem better or worse?

N/A

How long has your 2013 GMC Terrain had this problem?

I haven’t drove anywhere but the parking lot in a year.