Okay fellas, I've got that dreaded engine noise that sounds like something is knocking, or tapping, or rattling noise.

I've made some sound files up which you can get here (http://home.swiftdsl.com.au/~tecodan/magna_enginenoise/funny_noise.mp3) and it is definitely NOT the tappets since they sound like this (http://home.swiftdsl.com.au/~tecodan/magna_enginenoise/tappets.mp3).


Now I've heard that the flex piping off the exhaust can make some sort of buzzing or rattling sound. Could it be this? I can assure I don't hear buzzing noises though.

My old man reckons it could be the big end bearing, and it does sound like its coming from there. In fact this noise was first apparent when I changed the alternator and power steering belts because they were squeeking loudly. Now that the squeeking noise is gone, I can hear the sound above, though I don't know whether it started happening when I changed the belts or it has always been there but muted due to the louder belt noise.

Damnit this is so annoying...


Edit: The noise appears once the car has warmed up....

Edit 2: I forgot to add, this is on the TH Magna with the 3.5L motor

The noise sounds very "metallic" and is a knock in time.
You said it started after you tightened the belts so check all the belt driven accessories and tensioner pulleys for wear in the bearings by giving them a spin with the belts off.
does A/C on/off affect it?
It could also be a worn front main crank bearing knocking because of the extra tension on the belts pulling the crank off line.

Dan,
I havent heard your file, but the sound and location you are describing sounds like the idler pulley between the alternator and the a/c compressor. Some people also mentioned that "your mains are rooted :doubt:" . However, i renewed the belts and removed the tensioner, and the sound went away.
BTW, the belt u have on there now will be fine to re-use.

CHris