This noise use to be low but today it got so loud when I was driving here is a video of the noise

 

are you talking about the clanging noise or the whomping noise that could be loose flywheel bolts

 

If there are flywheels in autos then it could be. (I use to be 5 speed only guy never really did research on auto trannies)

Basically the metal noise after I close my door and couple seconds under the vehicle then it stops while I was recording under the vehicle.

not the clogging the other noise.

 

the metal clanging on metal sound sounds like a heat shield on the cat

 

I will take a look after the xj cools down and see if it is loose

any one else think it is something different?

 

it just sounds to much like a loose heat sheild to me to think its sometyhing else

 

I checked the heatshield on the cat converter and it is fine. it does it when I drive but it sometimes does it when I am parked could be a belt pulley?

 

when you chexked the shield is the exaust it self moving around easily

 

Sounds like your cat is shot, could be wrong hard to tell in the vid but just go hiting **** underneath until you replicate the noise...(seriously)

 

will do but I am little nervous I may break something.

 

put on some oven mittens and start pushing on things, sounds like the muffler/ exhaust manifold bagging on something to me

 

Will do. I did notice when I say in the XJ the noise started then when I got out couple of seconds later the noise stopped.

 

Still in need of help to locate it. I have been told it could be flexplate which will **** me off since the previous owner "claimed" the transmission got swapped and rebuilt.

 

Quick update I checked the flywheel bolts and they are all tight. I noticed a heatshield that seems to be loose on the exhaust manifold its like T fitting.

like top part of T is on the exhaust and the bottom part has cylinder type deal on it. Anyone know if there is suppose to be rubber hose on it that is suppose to go to the air intake box? its the same diameter as the exhaust pipe (the bottom part of the T.) Lets hope thats the noise I think I may just clamp it down but it is hard to reach.