ZF BMW Spark Plug 12120037663 LZFR6AP11GS Iridium Long Life

When your BMW experiences intermittent rough idle, weak acceleration, or noticeably increased fuel consumption, or even cold-start difficulty, this often indicates the spark plug electrode gap is too large or carbon buildup is severe; replacement is required. This spark plug precisely ignites the mixture to ensure smooth power delivery, reduced emissions, and better fuel economy. OEM numbers 12120037663 and LZFR6AP11GS; fits many post-2000 BMW models such as 3 Series (E46), 5 Series (E39/E60), and X5 (E53). Use a torque wrench to tighten to manufacturer specification to avoid damaging cylinder head threads or causing leaks.