It was about 19ºF this morning, and when I started the car, there was a relatively loud snapping/popping sound followed by grinding for a few seconds at a time intermittently for about a minute. I assume this was the compressor.

I didn't get any warning messages on the dash. From what I've read, the air compressor ends up freezing in very cold weather and gets "jammed" or stuck. My question is, should I purchase a new air compressor as a backup? Or should I wait until it fails? From what I hear, the repair is fairly quick and straightforward.

I guess my real question is will it fail gradually, or will one day it just crap out on me?

 

Your car's age and the current weather conditions do leave it ripe for a suspension compressor failure, but you should really investigate it further. The noises you heard, were they coming from the area below the left headlamps? That's where the compressor is located.
Compressor failure is most often preceded by "Air Suspension Fault" messages on the instruments, unless the failure is hard mechanical, which could completely stop it's function abruptly.
Whatever the case, what you describe should be looked into.....soon.

Cheers,

 

They were coming from the passenger front side of the car (as heard from inside). I just drove it again to lunch and everything sounded normal. Although it's not as cold as it was this morning.

 

That rather seems to rule out the compressor. I guess you'll have to reproduce and trace the sound a few more times.
Good Luck!

 

How does that rule out the compressor?

 

Here is an interesting thread I found that explains in great detail what is suspected to happen with the failing air compressors.

https://www.jaguarforums.com/forum/s...ad.php?t=10574

 

Because your compressor is in the wheel well in front of the left front tire.

 

Touche!! It's hard to tell exactly what the sound is, though, especially since I haven't gotten out of the car fast enough to hear it. All I know is that it's coming from the same area where after I shut the car off after a long drive, I hear what sounds like the winding down of a turbine engine.

Maybe I have been jumping to conclusions in thinking that it is the air compressor, especially since I have no "air suspension fault" message. However, I have dreamed a million times what the air compressor might sound like when it does finally start to show signs of deterioration and it sounded like that!

If I hear the sound again on cold start up, I will get out and see where it is coming from.

 

I guess it is time for me to step back from this thread. I can only offer an opinion, my opinion, based on symptoms you describe. Your air suspension compressor is located at the bumper reinforcement below the LF headlamp. You say your noises are from the RH side of the car. Rules out the compressor. You say you have no Air Suspension fault messages on the instruments, tends to rule out the compressor. You do not mention any ride height problems with your car. Seems to rule out the compressor.
I have read through the post you referred to and I have to disagree with some of the authors conclusions. [I do remember that letter he refers to, and the fact it did get to Jaguar Cars NA, it made it's way to a lot of folks] I have been with a dealer since well before the launch of the X350, and have worked on many of them for their entire life. I have found the suspension system to be rather reliable, and have seen few catastrophic repairs like they refer to. [makes me think they are going to someone not fully competent and are being told "it needs everything" when it really doesn't] I have found the compressor life to average 40-45K miles or about 5 years. I don't find that objectionable. Considering what it does and where it has to do it, I think that's pretty good. The price has been coming down as well, what used to be a $900 compressor is now around $600 or less. Too many people seem to think cars should last almost forever.....just not possible.
Posts like that one scare folks into thinking "that must be what's wrong with my car", or "these cars are junk", and that is a disservice. Someone competent needs to do the detective work and locate the true cause of the noise you experience, and make the correct repair.
Here's hoping that happens without them cleaning out your wallet.

Good luck!

 

I admit that I am a little bit paranoid about air suspension failures, and I apologize if I have jumped to conclusions. I did not mean to spread the paranoia, but I also feel that there could potentially be warning signs to air compressor failure PRIOR to receiving a warning message on the dash (but this may be unfounded). I appreciate your advice and opinion.

Does anyone know what the "turbine" like noise is that occurs after starting the car, and also sounds like it winds down when you shut the car off? This morning that sound was replaced with the "snapping/popping" sound I described. The turbine noise seems to only occur when I start the car on colder mornings, but this morning was the coldest morning we've had since I've owned the car.

 

That "turbine" sound took me a while to figure out, too. It's the radiator fan. Next time you start your car cold and have time to let it sit, you can hear the radiator fan wind up, wind down, and wind up in a gradual crescendo as the car warms up.

I think it sounds kinda futuristic and cool!

 

Hmmm, I guess it's possible that my radiator fan was frozen! I had just gotten a carwash at around 25 degrees, and I'm sure all kinds of moisture could've frozen on there.

I do love that turbine sound.