under the intake manifold you have to remove the engine cover to get to it.
Oldsmobile didn't make a Cutlass Supreme in 1998
Which engine?
The 3.4 liter V6 engine in a 1998 Oldsmobile Silhouette has a timing CHAIN
To access the spark plugs in a 1998 Oldsmobile Delta 88, first, open the hood and locate the engine. Remove any necessary components that may obstruct access to the spark plugs, such as the engine cover or ignition coils. The spark plugs are typically located on the engine's cylinder head, so you may need a ratchet and socket to remove them. Ensure the engine is cool before starting the replacement process.
Follow The TOP Radiator Hose From Radiator To The Engine. Where It Is Clamped On Remove The Hose. Behind The Housing Where You Removed The Hose Is The Thermostat
Remove the lower radiator hose.
Front, drivers side , below engine
4.6 US quarts
The starter of a 1998 Oldsmobile 88 is located on the passenger side of the engine, near the transmission bell housing. It is mounted to the rear of the engine block, making it accessible from underneath the vehicle. To replace or inspect it, you may need to remove some components for better access. Always ensure to disconnect the battery before working on the starter.
Remove fuel tank for access
To remove the intake manifold on a 1998 Oldsmobile Delta 88, first ensure the engine is cool and disconnect the battery. Remove any components obstructing access to the manifold, such as the air intake, throttle body, and vacuum lines. Unscrew the bolts securing the manifold to the engine, starting from the center and working outward in a crisscross pattern. Carefully lift the manifold off, taking care to avoid damaging any gaskets or attached components.