* The "Gadget": This is likely the ignition control module (ICM) or a similar component. The ICM is crucial for the ignition system. It receives signals from the ECM (Engine Control Module) and uses them to trigger the ignition coil, providing the spark to ignite the fuel-air mixture. A faulty connection or damaged wire to the ICM will disrupt this process.
* Symptoms: A bad connection to the ICM can cause intermittent engine failure, exactly as you describe—the engine running fine then suddenly cutting out. The clicking sound under the dash is often related to the relay or circuitry trying to engage but failing due to the poor connection or faulty ICM.
* New ECM: The fact that the problem started *after* the ECM was installed suggests that the problem might not be directly with the ECM itself but rather with the wiring or connection between the ECM and the ICM (or some other related component). Installing a new ECM could have jostled wires or created a new point of failure during the installation process.
What to do:
1. Inspect the Wire Thoroughly: Carefully examine the entire wire you found to be bad. Check for breaks, frayed insulation, corrosion, or poor connections at both ends. Even a tiny break can cause intermittent issues. Repair or replace the wire.
2. Check all connections: While you are at it, inspect all other connections related to the ignition system and any components associated with the ICM. Use a multimeter to check for continuity (a complete electrical pathway).
3. Test the ICM: After fixing the wire, it's a good idea to test the ICM itself using an appropriate testing method (consult a wiring diagram for your vehicle). This can determine if the ICM is at fault as well. Replacing it is relatively inexpensive.
4. Check the ignition coil: The ignition coil is another component that could be causing or contributing to the issue. A malfunctioning coil may cause poor spark delivery.
5. Check the distributor (if applicable): If your car still uses a distributor, ensure the distributor cap, rotor, and points (if applicable) are in good condition and properly adjusted.
If you're not comfortable working with car electronics, it's best to have a qualified mechanic diagnose and fix the problem to prevent further damage to the new ECM. Attempting repairs without proper understanding could lead to additional problems or even damage other vehicle components.
