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1994 Chevrolet Silverado 1500 won’t stay running

When we get it started it will not stay running

The ignition control module may be bad.

Ignition control modules function in two modes.

These are the start and run modes.

When starting the engine, the module allows full battery voltage to the coil to ensure a cold engine has a hot enough spark to start,

When the ignition switch goes to the run position, the module switches to the run mode.

The module then drops the voltage to the coil so when the charging system comes on line when the engine starts, the higher voltage doesn’t fry the secondary ignition components.

So, the module may be working during the start mode, but failing in the run mode.

Tester

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