i have 94 lt1 a4. i recently did a CC503 cam in my car and ive been driving it for weeks untill one day i started my car and when i came back out to leave i heard a strange metal clanking noise coming from under the hood. the noise is not consistant with motor speed and when i rev the car up i cant really hear it at all. also when i took it around the block the car runs smooth and has no miss or and vibrations, but when i hit the brakes hard i loose oil pressure for a second. is it likely my pick up fell off inside the pan and could be hitting the crank?

 

Definitely sounds like the pickup may have fallen off. Rap the bottom of the pan with a rubber mallet and see if you can hear it bouncing around. Or if you (or a friend) have a lighted borescope you could drain the oil and inspect through the fill plug.