dthdcrd wrote:
That's almost exactly how mine sounded. I was hunting it for a while until it got so bed it became obvious to find. I found a lot of carbon build up around the #4 injector. The oring, crush washer assembly was leaking. Do you have any exhaust smell in the cab? Check all your injectors. Put a 10mm on each of the bolts that hold the crows foot in place that clamps the injector down. You can also, carefully, push down on the top of each injector while running to see if the sound changes. Before mine got really loud and you could hear the exhaust leaking it started like a knock. I was thinking torque converter hardware and all kinds of things. Good luck it's worth a try.
Thanks I looked at this, and some of the injector bolts could have been tightened down, but no evident change and no obvious leak. So I stethoscope-ed around and it's still inconclusive, it's clearly louder on the driver side, and isn't the transmission. What surprised me is how much noise the motor mounts suppressed but yet how loud it is in the cabin. Stethoscoping the frame in random places wasn't helpful either - although perhaps I should try from inside of the jeep to see how the noise is being transmitted as it's really hard to verify there isn't a rock stuck somewhere against the body above the trans or between the motor and firewall.
Did you primarily hear the noise in the cabin? It's been like this for about 1k miles now and is still primarily evident by in cabin noise. The intake is noisy and pulses but no more so then our other liberty CRDs that sound fine.
I'll also try a compression test on it on the off chance one if the cylinders is low, which will prompt me to pull the valve cover and look.