I have a '97 1.8 NA Miata that was leaking oil around the cam angle sensor (CAS), so I had to replace the o-ring. It's located on the exhaust cam for the 1.8. The CAS on the 1.6 is located on the intake cam.
Part numbers:
CAS O-ring: 99541-03801
Hood stops: FB01-56-787B

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