Tools and Materials:
* New spark plug wires: Make sure you get the correct wires for your specific engine. Auto parts stores can help you identify the right ones based on your vehicle's VIN or engine code.
* Socket wrench set: You'll likely need a socket to remove the spark plugs (usually 5/8" or 13mm).
* Spark plug wire puller (optional but highly recommended): These tools make removing the old wires much easier and reduce the risk of damage.
* Needle-nose pliers (optional): Helpful for reaching tight spaces.
* Wrench (possibly): Some spark plug wires have a clamp-style connection requiring a wrench.
* Shop rags or paper towels: To keep things clean.
* Owner's manual (optional but helpful): Provides diagrams and specific torque specifications if needed.
Procedure:
1. Safety First: Disconnect the negative (-) battery cable. This prevents accidental shorts and protects you from electrical shock.
2. Locate Spark Plugs and Wires: The spark plugs are located on top of the engine, usually under a plastic cover (if equipped). The wires run from the distributor cap (if equipped) or coil packs to each spark plug. Locate the firing order diagram; this is crucial for correct reinstallation (typically found on the engine or in your owner's manual). Getting the firing order wrong can severely damage your engine.
3. Remove Old Wires: Carefully pull the old wires off the spark plugs. Use the spark plug wire puller if you have one; this will prevent damage to the wires or spark plug terminals. If they are stubborn, gently wiggle them back and forth while pulling. If you must use pliers, be very gentle to avoid damaging the wire or the plug terminal.
4. Remove Spark Plugs (Optional but Recommended): While you're at it, it's a good idea to replace your spark plugs as well, especially if they're old. Use the correct size socket and slowly unscrew each spark plug. Clean the spark plug wells to remove any debris.
5. Install New Spark Plugs (If Replacing): Screw the new spark plugs in by hand until snug, then use the socket to tighten them to the manufacturer's recommended torque (check your owner's manual). Don't overtighten; this can damage the plugs or threads.
6. Install New Wires: Connect the new wires to the spark plugs. Make sure they snap securely into place. If your car doesn't use a distributor cap, ensure the wires are firmly attached to the coil packs.
7. Check Firing Order: Double-check that the wires are connected in the correct firing order. This is critical for proper engine function. The firing order should be clearly labeled somewhere in the engine bay.
8. Reconnect Battery Cable: Reconnect the negative (-) battery cable.
9. Start the Engine: Start the engine and listen for any misfires or unusual noises. If there are problems, double-check the firing order and wire connections.
Important Considerations:
* Distributor Cap (If Applicable): If your Buick Century has a distributor cap, replace the cap and rotor at the same time as the wires for optimal performance. Be careful when handling the rotor; it's fragile.
* Coil Packs: If your engine has coil packs, be very cautious when handling the connections to avoid damage.
* Firing Order: The firing order is critical. Double and triple-check this. Incorrect firing order will lead to very poor engine running.
If you're uncomfortable performing this task yourself, it's best to take your vehicle to a qualified mechanic. Improper installation can cause serious engine damage.
