1999 vt s pack rattle when idleing

[serotz]

i have a 1999 holden vt commodore, once the car idles until it is warm it begins to rattle from the engine, once i put the car into gear and start driving the rattling stops. I had a listen with the bonnet open and thought it was the tentioner pulley bearings, but once i replaced the pulley the noise was still there. It is hard to tell where the sound is coming from, it sounds like it is either deep inside the engine or towards the back and bottom of the motor. I have read that it may be my exhaust manifold heat Shields, I am not 100% what they are, but i have looked at the manifold and cannot see any sort of shields around them. Does anyone have any idea what my problem is?

[Not_An_Abba_Fan]

If it is a V6 it won't have heat shields. It could be the catalytic converter that is rattling. Get under the car and give it a thump and see if it rattles. Loose flange bolts where the engine pipes connect to the manifolds will also cause a rattle.

[10WVN]

could even be where it goes over the diff, i dropped one of the mufflers on my vn and from time to time got a rattle

[serotz]

sorry for the late reply, yer i gave the catalytic converter a hit couldn't really here anything rattleing. ii think i just need to get under the whole car and check for any loose bits, or go to the mechanic. thanx for you help.

[S.T.K.E]

Keep us posted for this if you can. I have a similar rattle that i can't diagnose.

[nathanVY]

my VS was rattling sometimes at traffic lights, then I changed my whole exhaust and headers, havent heard it since. So I think we can assume it was my exhaust