Hi All,

This is my first post on the forum (as well as my first Jaguar).
I've been a Porsche guy and PCA instructor til now. I've owned quite a few Corvette's as well.

I just picked up a 1998 Carnival Red XJR.
I am absolutely in love with the car, it's in great shape and looks absolutely beautiful, the X308 body combines the classic Jag look to the modern curves and elegance of today's cars in my opinion.

The car's service records checked out great, and I just did an oil change myself when I brought it home. It's at a body shop right now for some paint correction on the hood.

My issue is that from the inside, when the car is moving no matter at what speed you're moving, there is a constant whine. I know so much that it's not the supercharger whine because it isn't in sync with the rev's. It's just one whining noise that doesn't change no matter what gear you're in. It's neither subtle nor obnoxious. But after watching XJR videos on YouTube I think it's safe to say it's not the beautiful eaton supercharger wine.

On an XJ8 I drove in the past I would hear the motor, just the V8 operating as it should. So naturally I expected that at slow speeds and nice tame driving I would hear a bit more quiet motor noise. I can't even hear the supercharger whine with the rev's.

The car drives fine, there aren't any codes, trans shifts as it should, and the power is all there. It's just one (starting to get) annoying whine whenever the car is moving at speed. I can't hear the purr of the Jag motor as I'm used to nor the whine of the supercharger as I was very excited to hear.

Does anybody know what this could be?

Any and all input would be highly appreciated.

Thanks in advance.

 

You can remove the supercharger belt and drive around to 100 % rule it out. Overall if the whine does not change pitch with engine revs than you ruled out a lot components. There are the pumps for the supercharging cooling circuit and the heater core that you could check

 

Wheel bearings or noisy tires?

 

I know this may sound dumb, but where can I find how to remove the belt? I did a few searches and didn't find much. Is it a simple procedure?

Thanks again

 

Unfortunately ruled out. New hubs were done 1200 miles ago.

 

There's a 1/2" square hole in the tensioner. With a 1/2" breaker bar or ratchet rotate the tensioner clockwise to take pressure off the belt
http://www.2carpros.com/questions/ja...ry-drive-belts

 

Are you sure it is coming from the front?

The differential will transmit through the rear suspension if it's making noise ? Have you checked the fluid?

You can normally tell by getting it up to 50mph on a very smooth road -- on and off throttle will give you a change in tone.

Some people have also reported fuel pumps -- but that would happen with the car stationary.

 

Unfortunately, this isn't always the case. A cheap wheel bearing and/or the installer very well could have done a poor job of pressing the bearing into the knuckle or the hub into the bearing. It's a tedious job that can go wrong if not done properly.

If you are driving along and there's nobody around and you are doing about 45 mph, put the transmission in neutral and let it coast. If the noise goes away, the problem is in the transmission. If it's still there, I would look into the driveshaft center support bearing.

 

Thank you very much for that. Hopefully I can run it for a little without the belt to see if I hear it. Much appreciated. Now I just need to wait for the body shop to finish the paint correction on it.

 

Yes, I am certain it's coming from the from. Jaguar did the fuel pump about 1800 miles ago. I will definitely try letting off at 50 when I get the car back.

Also, this may sound even more dumb...how do I check the diff fluid on these, is there a bolt on the dif or an easier way?

Many thanks

 

Jaguar did the hubs so I'm hoping they did it correctly for what they charged me. Lol.

That's frightening if it's the trans. I know it has the MB tranny but would I smell something, I've driven it just under 1000 miles. Also wouldn't I feel it shifting? Right now it shifts like butter and the sounds doesn't run in sync with the gears.

 

Are you saying the sound does not vary with the car speed? I know you say thet it only happens when moving, but are you sure?]

I am thinking fan motor or either of the electric coolant pumps. I guess the ABS motor could be running too, but that should certainly give a fault. The stepper in TB is known to whine on these cars, too but I cannot believe it would be as loud as you describe.

Good luck. I hope you find it before it drives you insane!

 

Yes! the sound does not vary, I mean it get's louder as you get on the freeway, but it's a monotone whine pitch. Kind of like an older orange juice maker except throatier lol.

Thanks for that. I definitely need to take it to my indy when I get the thing back because I've learned it could be pretty much anything at all haha.

I'm hoping for the best. I'm surprised I haven't had a single issue with any of the 911's I've owned and they're notorious for problems (IMS bearing/RMS leak, etc).

Thanks again for your help.

 

Sorry to bring back this thread, but I just got back from picking the car up from the body shop. Paint correction came out awesome, the carnival red looks like a mirror. Also ordered clear lenses for the front bumper turn signals.

Shifted into neutral while driving and noticed no difference (other than the RPM going down to idle).

Since it's dark here now (7:50pm) I can't do it til tomorrow, but by taking off the supercharger belt and assuming the sound goes away when I'm driving without the supercharger (honestly didn't know I could do that, I've been around n/a cars too long), and the sound goes away, would that entail that there is something wrong with the supercharger and I am damaging it by running it? Or would I possibly need a new belt and tensioner? (belt isn't cracked upon visual inspection).

 

Thanks for your reply,

If it were a fan motor wouldn't I be able to hear it when the vehicle is stationary? as well as the electric coolant pumps

 

Turn the ac/heat off, no fans.

Pull the ac pressure switch so cooling fans aren't running.

Both of these fans are constant speeds.

 

Hey all,

I made a YouTube video (49 seconds) of moderate driving.

You can hear the noise, it's what sounds like an orange juice maker. Disregard the clunks as they may be from the road/my hand/indicators. Also sorry about the rain.

Anyone have an idea of what this could be?

https://www.youtube.com/watch?v=nW1m...ature=youtu.be

 

If it's the supercharger -- or the alternator you will get the noise when the car is stationary and the RPM's are increased. I can't see how this would be the cause since you put the car in neutral and said the sound did not change.

The transmission's pump can make a noise .. that will rise and fall as the transmission shifts -- it did not seem to do that.

I think you may be back to tires or driveshaft/ differential.

 

Listened to the video. Sounds like drivetrain to me. Sounds like the rental I drove recently with horribly cupped tires. Wheel bearing, differential, or transmission? This is a major drivetrain bearing on the way out.

It's not monotone, it's clearly varying with vehicle speed, not with engine speed.

Question is : what happens if, say, you are driving at a steady speed, and change down gear, manually? Then put it in neutral? Edit : I see I'm about the 4th person to suggest this.

The classic wheel bearing test is to drive in a straight line at 50 mph, and weave a bit. Noise should come and go as bearing is loaded and unloaded.

Actually, it REALLY sounds like a wheel bearing. Worst one I've heard!

Question : why are you driving with your fog lights on in the rain?

 

Thanks for the reply,

See if I'm driving and slip it into neutral the sound is still there so yes, my mistake, it doesn't vary with engine speed, rather vehicle speed.

As for weaving slalom style I haven't tried, but a few pulls to the left & right and nothing changes.

Definitely a drivetrain issue. Now I came across a thread where the guy changed his diff oil and all was well, no more sound. It's definitely coming from the back. But as for tires, they're brand new Michelin pilot sport's.

So via forum diagnosis would it be safe to say that its either a rear wheel bearing or the diff oil?

Lol it's been a foggy past few days here on the east coast...we've been having quite a nice spring this winter