Here's a general guide. Specifics may vary slightly depending on the engine (e.g., 1.8L, 2.0L, 2.5L) and trim level. Always consult a repair manual specific to your Cavalier's year and engine for detailed diagrams and torque specifications. A Haynes or Chilton manual is a good investment.
Tools You'll Likely Need:
* Socket wrench set (metric)
* Ratchet
* Extension(s)
* Possibly a spark plug socket (depending on coil placement)
* Pliers (for disconnecting connectors)
* Wire brush (optional, for cleaning terminals)
* New ignition coil (ensure it's the correct one for your engine)
* Gloves (recommended)
Steps:
1. Locate the Ignition Coil: The location varies depending on the engine. On many 1991 Cavaliers, the coil is usually mounted on the valve cover or near the distributor (if equipped). Consult your repair manual for the precise location.
2. Disconnect the Battery Negative Terminal: This is crucial for safety.
3. Disconnect the Ignition Coil Wiring: Carefully disconnect the wiring harness connectors attached to the ignition coil. Take note of how they connect to make reassembly easier. You might need to gently pry the connectors apart with a small flat-head screwdriver or your pliers.
4. Remove the Coil Mounting Bolts (if applicable): Some coils are held in place with bolts. Use the appropriate socket to remove these bolts. Others might simply clip into place.
5. Remove the Old Ignition Coil: Once the bolts (or clips) are removed, carefully remove the old ignition coil.
6. Clean the Mounting Surface: Use a wire brush to clean any corrosion or dirt from the mounting surface on the engine.
7. Install the New Ignition Coil: Carefully install the new ignition coil, ensuring it is seated correctly. Tighten the mounting bolts (if any) to the manufacturer's specified torque.
8. Reconnect the Wiring Harness: Carefully reconnect the wiring harness connectors to the new ignition coil, ensuring they are securely fastened.
9. Reconnect the Battery Negative Terminal: Reconnect the battery negative terminal.
10. Test the Ignition System: Start the engine and check for smooth running. Listen for any misfires or unusual sounds.
Important Considerations:
* Distributorless Ignition Systems (DIS): Many 1991 Cavaliers utilize a distributorless ignition system. In these systems, the ignition coil is directly connected to the spark plug wires. Be extra careful during disconnection and reconnection.
* Spark Plug Wires: While replacing the coil, inspect the spark plug wires for damage or wear. If they appear cracked, brittle, or worn, replace them as well to prevent further ignition problems.
* Professional Assistance: If you are not comfortable performing this repair yourself, consult a qualified mechanic.
This is a general guide. Always refer to a repair manual specific to your 1991 Chevy Cavalier for detailed instructions and diagrams. Improper installation could lead to engine damage.
