Hey guys, I have a '99 Xj that is making a sound when I idle. The sound is a sort of popping rattle coming from the lower portion of the engine (maybe rearward?). You can also feel it in the floorboard.

I want to mention that the exhaust pipe right after the manifold is crushed and restricting flow. I don't know if the back pressure would create this sound?

Any help would be appreciated!

P.s. Sorry for the poor quality video. The rattly Boise is what I'm hearing. I have my phone placed up against the transmission hump near the gas pedal.

https://youtu.be/juV8hP5wYmU

 

Check the flexplate for cracks near the hub or loose torque converter drive bolts.

 

Believe it or not, it came that way from the factory and is normal. It won't cause any problems.

 

I will take a look this weekend. Fingers crossed it's just a loose bolt; I would think that if it was a crack the noise would be more rhythmic?


That's interesting, I've never seen that before. Do you know the purpose of that?