From what I'd read a while back, there may be version of the port that had a permanently installed valve, designed to be replaced as an assembly.

I'm not sure if this is the case with your car, and that particular valve, but it may be. If I remember correctly, it was mostly the later model US makes that were doing this, but who knows.


I also seem to remember a 'replacement' adapter that was to fix those, that installed over the valve, depressing/opening the faulty valve, and putting a new one above it.

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-Josh
Testing the cheap Mercedes axiom, one bolt at a time...