hi

my brother has a mk4 escort rs turbo, the engine was rebuilt 3000 miles ago and has started rattleling which sounds like its coming from the head (it had new ford cam and tappets).
oil pressure gauge readings seem all over the place, from start up it reads 40lbs then goes to 55lbs when reved.
warm idle is 35lbs and when driving 35lbs but when it gets to hot idle its 15lbs.

what could be causing these strange readings?

any help would be great
cheers
mark