Failing to find the manual, you can try:
* Looking up your vehicle's VIN: Many online parts stores (like AutoZone, Advance Auto Parts, etc.) allow you to enter your VIN to get the exact specifications for your vehicle.
* Checking a reliable online repair manual: Sites like Chilton or Haynes offer repair manuals that often include this information.
Do not attempt to guess the spark plug gap. An incorrect gap can lead to misfires, poor performance, and damage to your engine.