I have a 2005 XJR still (barely) under the Select Edition warranty. I hear a clunking noise from under the hood that can best be described as sounding like a "jawbreaker" piece of candy banging around in an empty coffee can. It is a hollow, deep clunking noise. It takes place when making sharp right turns, whether braking or not, and the noise has a notable pendulum effect. It will start with louder, deeper clunks and then it will trail off with a few lighter clunks. It can also happen when coming to a straight stop, but not nearly as bad as when turning. I have had the car in to the dealer twice now, and naturally I cannot replicate the noise when the tech takes a ride with me. It will happen all the time for a week, then be perfectly silent for a few days, then it comes right back.

If anyone has a suggestion, I would really appreciate it. My dealer is over an hour away and their service guys are only there Monday-Friday during business hours. I cannot take more time off work to get there and not have the noise reappear...

Thanks!

-Tom

 

Can you link any event to when the noise started; for instance have you just had it serviced ?

A mechanic may have left a tool somewhere under the hood, and its now banging around. Look under the two covers at the back of the engine compartment, and look around the engine compartment with a torch for anything obviously loose. In aircraft maintenance, there is normally a tool count after completing work to ensure nothing is left to cause havoc when the plane is flying.

 

Whenever I hear the description 'clunk' I think of the sway bar bushings, which are very common items for replacement. Now, the ones that I have remedied on mine did not vary in volume, but almost always on a stop when there was a ripple in the pavement or small bump. For some reason, the RF bushing got the worst wear and it was evident it was bad upon inspection. Easy to spot too, just get under the front and take a peek, nothing to spoil the view.

 

I have a clunk over bumps and is louder over bumps in a turn. I think the shock system on my air compressor is bad. Does it sound like it coming from the front driver side like mine? I removed the air filter and used a large screw driver to move the compressor. It had alot of play. Also, is it slightly delayed from the suspension noise?

 

A couple of things - Actually answering two posts.

First, on the clunking noise when turning and braking, check that the brake pad retention springs are there and not missing.

On the air compressor, it is mounted on four coil springs so it floats in position. Otherwise, the action of the compressor would make a chattering sound every time it come on. The movement is normal.

 

I changed the brakes and they are good. My sound is alot deeper and I think the dampener system is weak that supports the compressor. It has to much play and moves to easily. It should reduce vibration from the pump and not create noise.

 

I'm going to give it a thorough look this weekend. I appreciate everyone's ideas- I'll report my results soon.

 

tlombard77, keep us posted! Let me know if you need a extra set of hands, I think we live close to each other.