1998 Oldsmobile 88LS 100,000 miles engine shuts off

1998 Oldsmobile 88Driving down the road engine just shuts off. Sometimes it starts right back and sometimes not. All electric still functions. No check engine light comes on.
Problem is sporadic. Possible coil pack? Plugs and wires have been changed. Seems to be more electronic than a fuel system problem.


Engine shuts off

Sounds more electrical to me as well. Difficult to pin point the cause on these intermittent problems. When it won’t restart is when you can perform some tests. Since it doesn’t happen all the time it is difficult to diagnose. My GUESS would be a failing ignition control module or crank sensor/wiring harness. The ignition control module is directly underneath the coils.

Ignition Control Module Replacement

Removal Procedure

•Disconnect the 14-way connector from the ignition control module.
•Disconnect the spark plug wires from the coil assemblies.

ignition module 1998 Olds 88•Remove 6 screws (1) securing the coil assemblies to the ignition control module.
•Remove the coils (2) from the ignition control module (3).
•Take off the ignition control module.

Installation Procedure

•Attach the coils to the ignition control module. Refer to Ignition Coil(s) Replacement .

Caution! Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.
•Install 6 ignition coil attaching screws

Tighten the screws to 4-5 N·m (40 lb in).
•Install the nuts and washers securing the ignition control module assembly to the mounting bracket.

Tighten the nuts to 8 N·m (70 lb in).
•Connect the spark plug wires.
•Connect the 14-way connector to module.