Blew the stainless-steel fuel line.

[Zplz]

I thought this would be an interesting post. But I have a very modified car, and I regularly go out racing on the weekends. On the way back I smelled some E85 and popped the hood. Check this out! Guess the OEM stainless steel line cannot handle the prolonged pressure overtime. Will need to find an aftermarket replacement that can handle it. But for now, I replaced it with an OEM part for 150 bucks. Part number is 17520-6GP0A if anyone is interested but was told by the dealer to probably buy a few spares before any aftermarket replacements come about. Glad there was no fire!

Update 3/16/26: On my third line keeps breaking at the same spot on the copper. No aftermarket replacement yet.

Out of curiosity, I tried looking in that area, without taking off the cover. It appears you can see the connection in question, at least where it looks to be spraying from in the video above, if you shine some light in the area under the cover from the driver’s side. No problem noted with mine, for now. Something you can keep an eye on, when you’re checking the oil, as a minimum.

 

[Drago86]

It looks like it goes from that screw on fitting into a distribution block, then splits to the fuel rails, and the fuel rail connections are hose clamps, so I assume there's not a crap-ton of pressure on it...fuel pressure, I guess (60psi?...idk).
It would be possible to fab a quality fitting, but I don't know what's going on in that block (whether it's a straight-through split, or there's something fancy in there).

This car is direct injection, its close to 3000psi peak going into the fuel rails.



Also, I imagine this part is the same as all the other vr30ddtt engines, could it just be manufactorering issues? Ill try to cross check the part number to the q50/60 part vr30ddtt(unless someone knows already)

 

[FSUZ33]

Thank you for correcting me!

I guess I’m thinking about rail pressure of port injection.

Also just looked up pics of that crossover line. The “drawings“ from Nissan I was looking at made it seem like the ends that connect to the rails were flared for a hose and clamp, but they’re not. They’re the same type compression fittings as the one at the high pressure fuel pump (the leaky one above).

 

[bpeckham]

I did some googling, but I didn't find much failure info on the VR30DDTT in the Q50 Red Sport. Did anyone else find data on this?

 

[Zplz]

I did some googling, but I didn't find much failure info on the VR30DDTT in the Q50 Red Sport. Did anyone else find data on this?

Just this, via Google A.I.

“A fuel line leak in an Infiniti Q50 Red Sport (equipped with the VR30DDTT engine) is a high-priority safety issue that requires immediate attention. Because the Red Sport uses a direct-injection system with both low-pressure and extremely high-pressure lines, a leak can lead to engine fires or significant performance loss.

Common Leak Locations

• Low-Pressure Line to High-Pressure Fuel Pump (HPFP): A frequent failure point is the connection or the "black and red component" (often a quick-connect fitting) on the line feeding the high-pressure pump.
• High-Pressure Fuel Pump (HPFP): The pump itself can fail or leak at the sensor seals. Caution: Do not attempt to crack open high-pressure lines while the engine is running or recently turned off, as they contain dangerous levels of pressure.
• Fuel Rail & Injector O-Rings: Leaks can occur where the fuel rails meet the injectors, often manifesting as a strong raw gasoline smell under the hood.
• Aftermarket Components: If your vehicle has an
  AMS Performance Flex Fuel Kit
  or similar mods, check the AN fittings and braided lines for looseness or wear.
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Symptoms to Watch For

• Strong Gas Smell: Especially noticeable through the vents when stopped or idling.
• Hard Starting/Extended Cranking: Fuel pressure bleeding off while the car is parked causes the engine to struggle to fire up.
• Visible Puddles: Check the ground under the rear (tank area) or the front (engine bay) for amber/clear fluid that smells like gasoline.
• Performance Issues: Bogging, rough idle, or "fuel cuts" during hard acceleration.
  YouTube +6

Actionable Steps

1. Do Not Drive: If you smell raw gasoline or see a puddle, do not start the car. Gasoline is highly flammable, and engine bay heat can easily ignite a spray from a pressurized line.
   Morin Brothers Automotive +1
2. Visual Inspection: With the engine off and cool, remove the engine cover and use a flashlight to look for "wet" spots around the silver high-pressure pumps and the rubber lines leading to them.
   INFINITI USA +1
3. Check Service History: Infiniti recommends inspecting fuel lines every 20,000 miles or 24 months. If your car is still under the Infiniti Basic Warranty, this may be covered.
4. Professional Repair: Expect costs to range between $300 and $500 for simple line replacements, though complex high-pressure pump repairs can exceed $1,000.”

 

[Drago86]

It looks like their(q50) part number was 17520-5CA0A, which looks like an identical part.

Photos of the Q50 part from fleabay:

If the current parts are experiencing some sort of quality issue, perhaps you can buy one of these 100k mile veterans from ebay to fix your car until Nissan gets their manufacturing in line.