The Fuel Injection Hard Lines have cone shaped male ends on the Tubing with a Female Nut. If one of those is leaking it is most often that the Steel Tubing is cracked or has developed a pin hole.

While either problem can happen anyway the cause is most often that the Fuel Injection Hard Line Clamps are broken or missing and the Hard Line is damaged due to vibration.

The cure is to replace the whole Hard Line and make sure all of the Hard Line Clamps are applied properly and are all there.

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84 300D, 82 Volvo 244Gl Diesel