The recommended spark plug gap for a 1999 Pontiac Grand Prix depends on the engine. You'll need to consult your owner's manual for the precise specification. The manual will list the gap based on the specific engine (e.g., 3.1L V6, 3.8L V6).
Without knowing the engine size, I cannot provide the correct gap. Trying to find the gap online without this information may lead to incorrect settings and potential engine damage.
