Dodge Pickup

You're probably hearing hot exhaust parts cooling down.

Any time the Check Engine light turns on there will be at least one diagnostic fault code stored in the Engine Computer. If you have a digital display odometer, the codes should show up there, otherwise you have to count the flashes of the light. Cycle the ignition switch from "off" to "run" three times within five seconds without cranking the engine, then watch the odometer or light. If the light flashes it will typically flash once, then there will be a pause, then two flashes and a longer pause before the next two-digit code flashes the same way. That's code 12 which can be disregarded. The last code will be 55 which just means "end of message". In '96 a new system began which includes four-digit codes so most likely they will be seen in the odometer. Holler back with those codes.

Caradiodoc