Before You Start:
1. Safety First: Disconnect the negative battery cable to prevent accidental shorts or shocks.
2. Consult a Repair Manual: A Haynes or Chilton repair manual specific to your Buick Century's year will give you diagrams, torque specs, and specific instructions. This is the single most important step to avoid damage or incorrect installation.
3. Gather Tools: You'll likely need a socket wrench (likely a 10mm or 13mm, check your manual), possibly a ratchet extension, and possibly a small flathead screwdriver (for stubborn connectors).
General Steps (Always Refer to Your Repair Manual):
1. Locate the Ignition Module: This is usually mounted on or near the distributor (if your 2.5L has one) or directly on the engine block near the ignition coil(s). Your repair manual will show you the exact location.
2. Disconnect the Wiring Harness: Carefully unplug all electrical connectors from the ignition module. Sometimes, a slight tug is enough; sometimes, you may need a small flathead screwdriver to gently pry the connectors apart. Take note of how things are connected so you can reassemble it correctly.
3. Remove Mounting Bolts/Fasteners: The module is usually held in place by one or two bolts. Remove these carefully.
4. Remove the Old Module: Once the bolts are out, the module should come off relatively easily.
5. Install the New Module: Carefully align the new module and install it in the reverse order of removal. Secure it with the bolts (don't overtighten).
6. Reconnect the Wiring Harness: Carefully plug the wiring harness connectors back into the new module, ensuring they are securely connected.
7. Reconnect the Battery Cable: Reconnect the negative battery cable.
8. Test: Try to start the car. If it doesn't start, double-check all connections and consult your repair manual for troubleshooting.
Important Considerations:
* Distributorless Ignition Systems (DIS): Many 2.5L Buick Centuries use a DIS system. In this case, the ignition module may be integrated with the coil pack. Replacing the entire coil pack might be necessary instead of just a module.
* Year Variations: The location and access to the ignition module can differ slightly across model years. This is why a repair manual is essential.
* Professional Help: If you're uncomfortable working on your car's electrical system, it's best to take it to a qualified mechanic.
By following these steps and consulting your repair manual, you should be able to replace the ignition module efficiently and safely. Remember, the repair manual is your key to success.
