1994 3.4 v6 loud tapping/Clanking loudest it seems at the passenger side exhaust manifold by oxygen sensor. No cracks or leaks, no egr leaks. Good timing chain. Oil pressure is good. No noise at idle. Noise which is like a clanking occurs slightly at 1500 rpms, 2000 rpms 2500 rpms and so on. The clanking actually goes away going up hills and the engine sounds great. Any ideas would be appreciated Thanks!

 

Check the exhaust Y-pipe where it goes across under the car, upstream of the cat. I chased a rattle for months until I figured out there's a pipe within the pipe that had come loose inside and was making an awful rattle. I pop-rivited the two pipes together and filled the holes with exhaust sealer. This is saving me about $350 (at least until inspection).

 

Yea, checked all that its got to be internal the noise sounds just like a fan hitting metal gets louder with rpms just about goes away at 3000 rpms. engine also stumbles alot during the noise and back fires sometimes

 

Can you do a movie? Knocking from mid engine not under load screams rod bearing to me.

 

Was able to make a video here ya go http://www.youtube.com/watch?v=cILgpemhIaQ

 

Wow I got a headache and the video did not help at all. The good new is from what I could make out it does not sound like an internal engine issue. Sounds like two things are touching on the outside of the motor that are not suppost to be touching. The down side is its going to be hard to help find it. I would start with a broom stick and just start feeling around and see if you and change the noise. Once you figure out where next task will be to figure out why. Normally this just a loose bolt or a cracked heat shield. It could also be a bad motor mount causing the motor to sit a little low.

Good luck.

 

kinda sounds like the exhaust is vibrating on another piece of metal but ya the vid is hard to hear

 

unhook the belt and see if that makes it go away. its not coming from under the car is it? im thinking idler, tensioner, alternator, power steering or a/c.

 

Man, I'm puttin my money (such as it is) on the alternator, sounds like the bearing. Can't tell if that whirring noise is from the engine or just extra noise from the video.

 

Thanks for all you help.....96 3.8 TEXAS I think i have the same situation you had..how far up the y to the engine did you rivet?