The 95 does not have an "IMRC unit".
The 95's system has an EVR and a dashpot to move the rod. Problems here normally cause the secondaries to stay open.
Since the original intake gaskets will be shot by now, a good cleaning of the intakes, throttle body, and gasket replacement should be in your future. This should fix any tendency of the secondaries to stick.
Your problem may not even be the secondaries. It may be fuel starvation, a vacuum leak, MAF problems...
Remove and plug the vacuum line to the dashpot or disconnect and pin the linkage open. This will keep the secondaries open at all times. See if the problem persists.
