Noise On 1990 Camery Help

[walbird]

Has any one observed this or does any one have suggestions as to cause or

solution,or is it a common fault.

1990 Camary V6 300 Km excellent condition

Noise started Happening over distance 4000 km gradual more pronounced and

dominant on a cold motor

Noise is louder than a normal running motor.

Noise similar to (a diaphragm type air pump at running at slow speed slow

speed) muffled pop-pop sound .

Noise is located close to or under Timing belt access cover lower rear side

of motor just above and left the Vibration damped crankshaft pulley.

Noise is dependent with motor speed but does not seem to effect performance

Fuel economy or idle or acceleration. but is getting louder

I have removed the belt to power steering pump as a guess but not the cause.

Noise is drowned out if motor is revved to say 3 000 rpm.