Spark plug tube. Porsche Boxster 986 / Porsche 996 3.4L  ❭  99610532552

Replacement spark plug tube with new o-rings.
This spark plug tube is engineered as a direct replacement for the original Porsche spark plug tube. It provides a sealed, precision-fit channel through the cylinder head for the spark plug, preventing coolant ingress while supporting proper plug alignment and ignition performance.
Sold individually, 6 required per engine.

Fits:
Porsche 986 Boxster / Boxster S 1997 - 2002
Porsche 996 C2 / C4 3.4L 1998 - 2001

Diagram ref no 27, 28 and 29.

The spark plug tube provides a protective and sealed passage for the spark plug through the cylinder head. It:
• Supports and protects the spark plug from contamination by engine coolant
• Prevents coolant intrusion into the spark plug well
• Maintains electrical insulation and correct plug orientation
• Helps preserve consistent ignition performance and combustion integrity

Spark plug tubes are subjected to age, heat, coolant chemicals, and vibration. Over time the tube can stiffen, crack, or lose sealing effectiveness, allowing coolant to seep into the plug well. This often leads to misfires, poor starting, coil damage, or electrical shorts, and is a common service item on aging Porsche M96 engines. Replacing compromised tubes with a high-quality OE Match spark plug tube restores the correct seal and prevents expensive ignition coil or wiring damage, especially during engine rebuilds, head gasket services, or preventative maintenance.

When to replace:
•  During cylinder head removal or service
•  Evidence of coolant in spark plug wells
•  Misfires or ignition issues traced to moisture/coolant
•  Cracked, brittle, or deteriorated tube material
•  Preventive refresh on high-mile engines

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99610532552

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