A quick look at the net shows the 2.2 is an inteference fit engine if the info is to be believed. This means bent valves and a major decision is looming.
There are several methods for determining this for sure. Line the cam sprocket up where the valves are (theoretically) closed on a certain cylinder, apply air pressure, and note if it hisses out the intake, remove the valve cover and check for excessive valve lash, etc.
At this point you need to verify engine damage beyond any doubt before spending one dime on parts.
You bought the car used and depending on your driving habits and environmental conditions going 6k miles between oil changes may be way too long. This can contribute to oil sludging or coking and it doesn't take much of this to damage a chain, tensioner, and quite a few other things. Removal of the valve cover could reveal some degree of this.
Chains do not take to dirty oil very well. As a motorcyclist I can tell you that the No. 50 chains on my Harleys are good for about 7k miles and O-ring chains maybe 10k miles+ although these drive chains are exposed to the elements.