i have a 94 interceptor with the 4.6 ohc and a good 180k on it. about 5 days ago i was driving and it started tapping like crazy. definately a top end tap. i have another car so i havent been driving it i have just let it sit while i thought about what could be wrong with it. i have started it up a few times and it still tapped. i let it run no more than about 30 seconds fearing catastrophic engine failure. i dont know to much about fords and i was wondering what this could be and any possible fixes for the problem keeping in mind it has 180k miles on it.