I have a 98 xj when I'm driving and I push the gas pedal in I hear what sounds like a tin can rattling under the hood as soon as I let off the gas pedal and the vehicle is coasting it goes away any thoughts?

 

Auto or manual? Does it happen only with high load? If you are cruising with light throttle it goes away?

 

Its automatic and it happens every time I'm driving even if I barely push the gas pedal in it dosnt go away unless I take my foot off the gas pedal

 

Pop the hood and with engine running pull the throttle cable. Can you reproduce it?

 

There is a heat shield on the exh manifold where its right under the intake ..mount points probably rusted

 

I figured it out! My AC compressor pully is the culprit. With throttle input the serpentine belt speeds up and causes the already slightly noisy pully to get louder. Any fix for this besides replacing the bearing or the whole AC compressor? Also the compressor is empty not sure if this would affect then noise at all.

 

I had the same nuts and bolts rattling sound and at some point would swear it was coming from the oil drain pan. Feared the worst. Turned out to be one of the pulleys from up front. Would have never guessed.