Where is auto shut down relay located on 87 LeBaron sedan?

There isn't a single component called an "auto shut down relay" in the typical sense on a 1987 Plymouth LeBaron. The system that shuts the engine down is more complex and involves several components working together, primarily the ignition system and the engine control unit (ECU).

Instead of a dedicated relay, the shutdown process involves:

* Ignition Switch: This is the primary component. Turning the key to the "off" position breaks the circuit powering the ignition system.

* Engine Control Unit (ECU): The ECU plays a vital role in controlling various engine functions. It receives signals from various sensors and based on those signals, it might shut down fuel delivery or spark, thus causing the engine to stop. This is especially true if the car has an automatic transmission or certain safety systems.

* Various Relays and Fuses: Many relays and fuses throughout the car's electrical system are involved in powering different parts of the ignition and fuel delivery systems. A failure in any of these *could* prevent the engine from shutting off normally.

To find the problem if your LeBaron isn't shutting off properly, you'll need to consult a wiring diagram for your specific model and look for issues in the ignition system, fuel pump circuit, and the ECU itself. A repair manual will be invaluable in this situation. Troubleshooting this without a wiring diagram is very difficult and could damage your vehicle.