Spark plug FR5DTC. Porsche 964 / 964RS / 993 / 993RS  ❭  99917018390

Spark plug, FR5DTC.
This genuine Porsche OE spark plug is the factory-installed ignition component in air-cooled and early liquid-cooled 911 Carrera and RS engines of the 964 and 993 generations. It provides the correct ignition characteristics for smooth, efficient operation, just as Porsche intended – ideal for service replacements, maintaining consistent performance and the authenticity of classic designs.
Sold individually, 12 spark plugs required per engine.

Fits:
Porsche 964 C2 / C4 1989 - 1993
Porsche 964 RS 3.6L 1991 -1993 M64.03

Porsche 993 C2 / C4 1994 - 1997
Porsche 993 C2S / C4S 1994 - 1997
Porsche 993 RS M64.20 1994 - 1997

Spark plugs are a critical part of the ignition system. Each plug creates an electrical spark inside the combustion chamber that ignites the compressed air-fuel mixture, producing the explosion that powers each engine cylinder. Genuine OE spark plugs ensure this ignition process is consistent, clean, and optimised - which supports smooth idle, strong throttle response, and efficient combustion throughout the rev range.

Functions & Technical Role:
• Ignition ignition source: Generates a reliable, timed spark for each cylinder
•  Optimal combustion support: Maintains a consistent burn for power, efficiency, and emissions
•  OE-matched heat range & gap: Designed to Porsche factory specifications for the 964/993 engine family
•  Durable construction: Quality materials resist normal wear and combustion deposits
•  High RPM performance: Suitable for classic 911 driving conditions

Spark plugs naturally wear from heat, combustion deposits, and electrode erosion. As they age, misfires, rough idle, and poorer fuel economy can develop. Installing Genuine Porsche OE plugs ensures the correct spark gap, heat range, and ignition performance, preserving engine efficiency, responsiveness, and emission stability.

When to replace spark plugs:
•  At Porsche-specified service intervals
•  During routine engine tune-ups or maintenance
•  If experiencing misfires, hesitation, or rough idle
•  When cold starting becomes harder than normal
•  If performance or fuel economy drops
•  While performing engine diagnostics or restoration work

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99917018390

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