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Start But Not Stay Running

The starter was replaced on a 1998 Oldsmobile Intrigue. The car will start, but not stay running.

The problem might be with the ignition module.

Ignition modules function in two modes. These are the START and RUN modes.

During the START mode, when the ignition switch is turned to the START position, the ignition module allows full battery voltage to the ignition coil paks to make sure a cold engine with a rich fuel mixture starts. Once the engine starts, and the ignition switch moves to the RUN position, the ignition module switches to the RUN mode. It’s here where the ignition module drops the voltage to the coil paks because it doesn’t require as much voltage to keep the engine running, and it also saves wear and tear on the secondary ignition components from operating at higher voltages.

So it could be that the ignition module is functioning fine in the START mode so the engine starts, but failing in the RUN mode where the engine dies.

Tester

Do you mean the ignition coil. I do not see any part called ignition module for a 1998 Oldsmobile Intrigue.

I am miles from top gun on this board. But, to me saying a car starts running then dies is like saying it has a funny noise. Anything is possible, including tester’s suggestion of ignition module problem.

Another thing that comes to my mind is the idle settings. I am assuming 1998’s all had Fuel injection, which means the computer controls the idle speed.

If the idle speed control is bad, you can start the car but it will die, because the idle speed is not kept high enough.

The way to check this is to start the engine while holding the throttle a tiny bit depressed, whereas we normally on FI cars do not touch the throttle, because the idle speed control takes care of it for us. This will let in enough air to run the engine fast enough to keep going. that is, if the idle speed control is bad.

Bad idle control is very common, and often missed by those looking for something harder.