One problem related to gas recirculation valve (egr valve) has been reported for the 1998 Oldsmobile Silhouette. The most recently reported issues are listed below.
Coolant leaked from gasket into engine degrading oil and resulted in extensive damage and cost. The downgrading began with this event. Il pump eventually clogged resulting in low oil pressure & repaired again. Eventually, engine self destructed, while on freeway, loosing power steering and power brakes resulting in near accident while exiting freeway. Then had to rent a Chrysler van to escape oncoming hurricane frances. This is more expense and aggrivation. All because of a faulty gasket leaking coolant into engine. This looks like neglegent design on gms part resulting in a catastrophic failure which could have resulted in death.