NISSAN 78836-50J00 Fuel Filler Door Spring

The genuine Nissan fuel filler door spring (part number 78836-50J00, SPR-FUEL FILLER) is a precision metal component engineered to ensure smooth and reliable operation of the fuel filler door.

Function and Operating Principle

This tension spring provides constant mechanical tension within the fuel door hinge mechanism. When the fuel lid release lever or button is operated from inside the vehicle cabin, the spring immediately and gently pops the lid open, allowing easy access to the fuel filler neck. In addition, it keeps the flap firmly held when closed, preventing rattling or unintentional opening while driving.

Common Symptoms of Failure

Over time, metal fatigue or environmental factors (moisture, road dirt, fuel vapors) can cause the spring to lose elasticity or break entirely. The most typical signs of wear include:

• The fuel door does not pop open when pulling the release lever, requiring manual assistance to open.
• The fuel door does not close flush, leaves an uneven gap, or vibrates during vehicle operation.
• Visually noticeable cracks, breaks, or severe corrosion on the spring surface.

Technical Specifications

• Manufacturer: NISSAN (Genuine OEM part)
• Part Number: 78836-50J00
• Part Type: Fuel filler door tension spring (SPR-FUEL FILLER)
• Material: High-strength, corrosion-resistant spring steel
• Installation Location: Fuel filler door hinge