low pressure port needle valve is leaking any way to replace? looks like a simple valve like a tire valve. 98 D with the 5.2

 

Some of those fittings are pressed and permanently sealed into the line and the entire line must be replaced. If it has a Schroeder type valve then it alone can be replaced. If it has the little black ball seat then no it cannot be replaced and entire line must be replaced.




Schrader valves are used on the “low-side” and “high-side” of the A/C system. The red and blue and yellow hoses of the manifold gauge set are attached to these valves to enter the system. The valves use a valve core that is screwed into the valve. When a leak has been found, a valve core removal tool to use to remove and replace a new valve core. This is the first area that a technician should look for a leak in the A/C system.
http://www.carspace.com/guides/Auto-...ing-Repair-101

 

What about a sealed cap if you can'r replace the needle?

Other than thet you might be able to snake one off a junker. Also check the O-ring on yours.