Tools You'll Need:
* Socket wrench set: You'll need a socket that fits your spark plugs (likely a 5/8" or 13/16" – double-check your owner's manual). A ratchet and extensions will make the job easier.
* Spark plug socket: This is a special socket with a rubber insert to grip the spark plug without damaging it. This is crucial.
* Wrench (for the plug wires): A small wrench to loosen and tighten the wire connectors on the spark plugs.
* Penetrating oil (like PB Blaster): Helps loosen stuck plugs. Apply this several hours before starting the job, if possible.
* New spark plugs: Buy the correct type and heat range for your engine. Your owner's manual or an auto parts store can help with this.
* Gloves: To protect your hands.
* Shop rags or paper towels: To clean up any oil or grease.
* Safety glasses: To protect your eyes.
Procedure:
1. Safety First: Disconnect the negative terminal of your battery. This prevents accidental shorts and protects you from electric shock.
2. Access the Spark Plugs: Locate the spark plugs. They are typically on top of the engine, under a plastic cover (often called a "valve cover"). You may need to remove the cover; there are usually fasteners securing it.
3. Disconnect the Spark Plug Wires: Carefully disconnect each spark plug wire one at a time. Note which wire goes to which spark plug – take pictures or draw a diagram if necessary. Use the wrench to gently loosen and remove the connector. Do not pull on the wires themselves.
4. Remove the Spark Plugs: Use your spark plug socket to carefully remove each spark plug. Spray penetrating oil onto the plugs if they're resistant to removal. Turn the socket counter-clockwise to loosen. Don't force it; if it's stuck, apply more penetrating oil and let it sit. You might need to gently rock the socket back and forth to break it loose.
5. Inspect the Old Spark Plugs: Examine the old plugs for wear and tear. This will give you an idea of your engine's condition.
6. Clean the Spark Plug Wells: Use compressed air or a shop rag to clean out any debris or oil from the spark plug wells.
7. Install the New Spark Plugs: Carefully screw the new spark plugs into the wells by hand until they are snug. Then, using the spark plug socket, tighten them to the manufacturer's specified torque. Overtightening can damage the plugs or the engine. Refer to your owner's manual or a torque specification chart for the correct torque setting.
8. Reconnect the Spark Plug Wires: Carefully connect the spark plug wires to the new plugs, ensuring each wire is securely attached to the correct plug.
9. Replace the Valve Cover (if removed): Reinstall the valve cover and any other components you removed.
10. Reconnect the Battery: Reconnect the negative battery terminal.
11. Start the Engine: Start the engine and listen for any unusual noises. Check for any leaks or problems.
Important Considerations:
* Torque Specification: This is crucial. Over-tightening can damage the spark plugs or the cylinder head. Under-tightening can lead to misfires.
* Gap: The gap between the spark plug electrodes is important for proper ignition. If the plugs came pre-gapped, you likely don't need to adjust it. However, check your owner's manual or the plug packaging for specifications.
* Heat Range: Ensure you're using the correct heat range spark plugs for your engine.
* Difficulty: Access to the spark plugs can be somewhat challenging in some vehicles. You may need to use extensions or swivel sockets to reach them.
If you're uncomfortable performing this task yourself, it's best to take your Astro to a qualified mechanic. Improperly installed spark plugs can cause significant engine damage.
