If you haven't changed the oil and the filter on the recommended basis, or used non synthetic oil, then there could be some sludge buildup.

I faced this same issue in my old '89 Probe in which I hadn't used synthetics.
I had to pull the rocker arms and use a set of carb jet drills to clean out the oil passages in the rockers.
( this engine is quite similar to the crossfire engine in that it is overhead cam with 3 valves per cylinder )
That fixed it's clicking.