By coincidence , today , I began tearing down the 2.5 in the 94. It's had the air raid intake on it for a year and a half , the filter is still pretty clean . I washed it with K&N air filter cleaner , it's set aside to dry , then will get re-oiled .
What's relevent , as far as this discussion goes is the throttle body , it's clean and will need nothing in preparation for re-assembly of the engine. This one is a mall crawler, Hammer down all the time but it is a pavment princess.
What's wrong with the 2.5 ? , nothing at all to do with the intake , it's been run hard & run low on oil repeatedly ( female driven) .
The 88 YJ see's use as a part time DD , trail use and whatever else I can dish out. I
The K&N that's on the 88 YJ , it's been cleaned once since I bought it and could use another cleaning here real soon , the water repellant sock does prolong the service interval.