have a low knock or ticking from top of engine not sure if it is coming from manifold or valve cover 100000 miles on car any ideas? when driving go faster as i speed up and slow when i slow down

 

Could be a number of things. You might want to invest less than $10 in a mechanic's stethoscope. It looks a lot like the kind the doctors use but has a metal probe for pinpointing noises like that.

What engine are we talking about here?

 

check oil level.

 

92, 5th ave 3.3 motor