For a lack of a better way to describe my ac on my 2003 xk8 convertible makes a "honking" noise occasionally. Really notice it when turning. It is not a power steering noise. Any ideas, help appreciated.

 

See if the pulley has some play, the bearing may be going. Or it may be the idler or tensioner bearing.

 

If it happens when turning, it could be one of the blower fans with a dry bearing. As you go around a corner, the spinning fan will try to resist the turn due to gyroscopic effect and can load up one side of the bearing, making it 'groan' if it's going bad. I had this with one of mine, so when I took the dash out to replace a leaking aircon evaporator, I replaced both with brand new fans just so that I didn't have to pull the dash again.

 

As both the A/C compressor and the power steering pump are on the same belt, I'd say it is time to inspect/replace it. After you remove the belt, inspect all accessories by spinning them by hand. Check for play, roughness, resistance, basically anything other than smooth. Replace parts are required. Or just throw in a new tensioner and idler pulley while-you-are-there or because of age.

Also, don't discard power steering noises. I'd say start with the easy procedure of gradually replacing the fluid by emptying the reservoir with a turkey baster and fill it with new fluid. Repeat a couple of times after running the engine for a bit. This will replace most of the fluid with new. Probably not as good as a real flush, but way easier to do.

On the theory of worn blower bearings, the system has 2 separate blowers, each with its own fuse. So you can disconnect one fuse at a time to see which blower might be a source of this noise. Check the chart, these fuses are in the "fascia" when you open the doors.

Best of luck, keep us posted.

 

Does it sound like the noise in this post?

https://www.jaguarforums.com/forum/x...e-my-c-228420/

 

No not at all

 

Thanks everyone I'll start on my journey. One last thing, at the beginning of summer it would not cool down so I put a shot of freon in it and leak detector. I did notice their was oily residue on shrader valve low port but I chalked this up to leakage putting in the freon, hard to hook up took a couple of tries. I used the recharge can type with the gauge in line so I don't think it is overcharged. AC cooled down after that but that is when the noise started. Is there any type od vave that might be actuating intermitantly that would cause the "honking" noise?

 

When a compressor bearing is beginning to fail there can be an occasional strange groan that resonates through the car. I recently put a reconditioned compressor in a BMW and experienced a weird sound. When I drained the oil from the compressor there were fine metal particles.