1. Gather the necessary tools and materials, including new spark plugs, a socket set, a ratchet, a spark plug wrench, and a gap gauge.
2. Disconnect the battery negative terminal. This step is crucial to avoid electrical shock during the process.
3. Locate the spark plugs. In the 1985 Nissan pickup, the spark plugs are located on the top of the engine, one for each cylinder.
4. Remove the spark plug wires. Use the spark plug wrench to carefully twist and pull each wire off its corresponding spark plug. Be careful not to damage the wires.
5. Remove the old spark plugs. Use the socket and ratchet to loosen and remove each spark plug.
6. Check the gap on the new spark plugs. Use the gap gauge to ensure the gap between the center electrode and the ground electrode is within the specified range as recommended in your vehicle's manual.
7. Install the new spark plugs. Screw in each new spark plug by hand first, then tighten it using the socket and ratchet. Be careful not to over-tighten the spark plugs.
8. Reattach the spark plug wires. Push each wire back onto its respective spark plug until it snaps in place.
9. Reconnect the battery negative terminal. Reattach the battery negative terminal to restore power to the vehicle.
10. Start the engine and check for proper functioning. Start the engine and let it run for a few minutes to ensure that the new spark plugs are working properly.
Remember, if you are not comfortable performing this task yourself, it is recommended to consult a professional mechanic or refer to a Nissan-specific service manual for your vehicle.
