Lack of oil lubrication to the valve lifters.
Somthing to do with the AC.
The most likely problem is the blower motor making the noise. It may be necessary to remove the box to find the noise for sure.
hydraulic lifters.
hey man i got a 2000 mercury cougar v6 it is makeing a tapping noise under my manifold, and i dont know what that could be. but it sounds like you might be haveing the same problem im haveing. suggestion: try checking where that tapping noise was again, it might be under your manifold!.
you would experience a pinging "metalic noise" under heavy or rush acceleration, would also have lost of power. this problem will not turn the check engine light.
It might be the CV joints. Go to a front suspension specialist and have it checked out.
something hitting the pipe, hot water pipe touching cold water pipe, or is it burping noise ? a tapping noise is sharp, do you live in an apartment ? is this a house, lot s of causes,
hydraulic lifter? Rocker arm?
Check the axle; it may be leaking/out of grease.
A tapping noise in a 2002 Camaro could indicated noisy lifters. Make sure that the oil level is full, and the oil is clean and recently changed. Lifter quieting additives can help reduce the noise some.
A tapping noise might come into the engine because of heat damage to the lifters of the motor. You might also hear a tapping sound if the engine has been damaged due to a blown head gasket.
Stuck hydraulic lifter.