Mysterious Rattle

[surfride]

Ive got an 04 Rubicon 5 speed w/ app 30k miles on it. Its got a rattle on cold startup audible for a couple of minutes, gone when driven a block or no rattle on warm-start. I am stumped and cannot find the source.

My first inclination was the throwout bearing, unfortunately, makes no difference with the clutch in or out. I picked up a auto-stethoscope to isolated the source with mixed results. Ive listened to; alt/ac/ps/idler/tensioner/starter have no unusual sounds. Checking the rear of the motor, its possible the sound is coming from the bell housing, rattle can be heard through the stethoscope. As part of vehicle maint every 5 years the cooling system is serviced including replacement of idle/tensioner and serp. Cooling sys maint was done in 2018, including a mopar water pump. I mention this because idler/tensioner/waterpump bolted on the fr of the engine are relatively new.

My concern is this may manifest into something serious.

A clip is up on youtube with the sound... YouTube

Thanks!

 

[JPNinPA]

Check exhaust pipe on oil pan.
You could have a loose exhaust bolt at the header at the manifold or loose manifold.

Also check the ODPA oil drive pump assembly.

Never look down on anyone unless you are helping them up - Jesse Jackson

 

[surfride]

Thank you for the advice, I had not heard of the OPDA issue... My OPDA does not look like an 05-06 version, much smaller... I put my steth on my OPDA on a cold-start and purrs like a kitten. Targeting exhaust manifold next. Thanks again.

 

[autonoob]

The most common reason why a jeep rattle are the ball joints, struts or strut mount, or a problem with the sway bar links.

 

[mark sr]

An exhaust rattle was my first thought.

 

[JPNinPA]

The most common reason why a jeep rattle are the ball joints, struts or strut mount, or a problem with the sway bar links.

Did you view the video? He is not moving only idling.


Never look down on anyone unless you are helping them up - Jesse Jackson