My '02 has developed a very strange noise. It's a 'pop pop pop' sound. Very tinny like the cat is ringing during exhaust pulses. BUT, it does this only under load. At idle in neutral/park there is no noise. Only when in gear. Louder when giving some gas and holding the brakes in gear but never loud.
It is NOT a rod knock or wrist pin slap. I know what those sound like.
The noise sounds like it is behind the cam belt covers on the top/front of the engine. 90K service and belts were change by Toyota about a year ago.
The noise drives me up the wall but doesn't seem to affect running. Engine is still smooth and otherwise quiet. V belts are new & tight. Water pump was changed when cam belts were changed.
Any ideas what it could be?
It is NOT a rod knock or wrist pin slap. I know what those sound like.
The noise sounds like it is behind the cam belt covers on the top/front of the engine. 90K service and belts were change by Toyota about a year ago.
The noise drives me up the wall but doesn't seem to affect running. Engine is still smooth and otherwise quiet. V belts are new & tight. Water pump was changed when cam belts were changed.
Any ideas what it could be?