Hi. I have a 96 Maxima SE with 136k miles. Starting at about 134k miles, I started noticing a regular tapping metallic sound when the clutch is not pressed down (foot not on clutch pedal). I do not hear this sound when pressing down on the clutch. When the clutch is not pressed down, I can hear the sounds in all gears and even in neutral. Sound seems to varies with RPM (tapping sound increases as RPM increases).
I couldn't tell where the sound is coming from. I heard a similar sound once on this car a long time ago (at around 30k miles) when we used the wrong gasoline (89 octane) that causes the engine to start knocking. At first I thought it was the same problem (let a friend borrowed the car and he might have used the cheaper gas), but I have re-filled about 4 times since with 91/93 octane and the sounds is still here...
Ideas on what to check??? I replaced the spark plugs at ~60k but haven't replaced them since. Could that help?
Ben