Hi all now weather in Uk has decided to become warm for the first time in the last 5 years have been driving around without the heater on. But I have noticed that I get a noise behind the dash. I It sounds like a fan on low speed that changes with engine speed. Its not there when sat at idle just when driving below 20. The noise is best described as when my Lexus GS started to drag one of the park shoes, it would make the noise at the top centre of the hub and then be quiet like out of balance theeeeww noise if that makes sense.

does the noise if ac is on or off, fan on or off, cooling fans on off, whatever gear I am in. it just seems to rise and lower with the speed. Its more annoying than anything as can just be heard in the background when the radio is off. Did a wedding a few weeks ago luckily they couldn't hear it.

PS the brakes are all new and not dragging and have the anti rattle clips that was the first place I checked.

 

I think I right in saying that even when the fan is set to minimum it is still running on this Jag.
Could it be the fan with bearings on the way out?

That's the only intelligent comment I can make I'm afraid.

 

your sort of bang on with the what it sounds like. When i get some time will see if i can pull the fuse just to double check that its not the fan.

 

Try turning off the heat/AC unit completely. If the sound disappears, you'll know it's the fan.

 

I noticed a fairly quiet whining noise that varied with engine speed when car was stationary, and had an air-con regas done. Noise disappeared. I think the noise was the compressor, and there was a lack of lube, (as well as gas, of course).

Turning off the climate control caused it to disappear.

 

Again good idea will have to have a look at that only thing is when everything is turned off still makes noise. Discounted the electrical connector to the blower motor today as still noise. It's a pain but it doesn't change with engine speed but with car speed.

 

just wondering if anyone else had any thoughts sort of taking the dash apart and going for a drive cant think of anything else.

 

Just thought would bump this post as it has been a while since I have been on the forum due to buying first house and work. Now I have to drive this car a lot more than before traveling this noise is really starting to get to me. So far I have check the fan the recon in the climate control, the compressor, ac compressor ,wheel bearings and other things. The noise is a whirring that only happens between first moving off and about 15 mph, it may carry on but road noise and stereo kick in. The noise is with car speed not engine I can put the car in neutral rolling and it still makes the same noise going up and down Witt the car speed.

Any help would be welcome I did read about an pully issue but I thought that would only make noise with engine speed.

 

Before I took anything APART I'd get a cheap microphone or several, make use of some tie-wraps and high-grade duct tape, and hunt-down the specific area the sound is coming from, and under what conditions.

If you record the audio into a laptop, you can even view the waveform later, see the shape and frequency in living colour, and have a reference from some other part of the environment on at least one other 'stereo' channel.

You may have all the needfuls under-roof already, so it need not be a costly exercise.

 

Thank you had a go at your suggestion and I think I have narrowed the noise down. I removed the j gate trim and placed a microphone there and before microphone was on I heard more noise. Also noticed car makes the noise in reverse went for a drive and pumped the tires up. I noticed that this didn't change the noise at all so it's not a wheel bearing as would have though would pick up slight change in the sound.

So my worries or what it sounds like to me is th prop shaft as I have an odd vibration at around 60 that vibrate through the car not the steering wheel. This may also explain when I put car into neutral while moving noise persists. So if anyone has any ideas or have heard about maybe the couplings if jaguar used cheap rubber or anything like that would be welcome as have been offered my farther s s type r for a good price but love the xj

 

Method having proven of at least SOME use, suggest you find yerself a smaller 'condenser' microphone - or strip one from some El Cheapo gadget - so you can put it onto a rod or soda-straw and probe into vents and such w/o having to take trim apart.

For engine, its helpers, and driveline, you may want to try taping a microphone flat onto to adjacent chassis.

As to rubber - I have had FIAT and BMW fail their flexible couplings. Those do not 'whine', they RUMBLE and thrash, and not just meekly.

I don't think your Jaguar even owns that particular failure-mode, but assessing what it does have wants being run whilst raised on a chassis, not wheel, lift, if the driveline is actually suspect.

I have great jackstands in my arsenal, but the days when I'd trust 'em well-enough to crawl under and use a running engine to re-face a flywheel whilst still on-crankshaft are ancient history.

 

May get the car in the air tomorrow with rear wheels of turn her on put in drive and have a crawl under least that was will see any movement . Never done this on a auto before (running it in the air) if the car is just in drive with no resistance idling away how fast will the engine go or can I leave in neutral and will still spin like a manual?

 

Not recommended. Really, not recommended.

However, the prop shaft will only spin when in gear and the engine will regulate at its normal idle point. At least warm up the car so that it is at a lower rpm.

Some of what you have written points at the centre prop shaft support bearing if you have one in that model.

You are better off to tape the microphone to the support bearing frame without the car running and go for a drive.

 

Yeh fed of the car now this noise is so annoying its getting worse with my traveling now. That sorta sound of putting a card in bike wheels as kid. Think will fine a nice local garage tomorrow offer them a bottle of scotch to whoever figures it out first. I need to get round to changing some of the front bushes and till I have this sorted I don't want to spend anything.

 

Done it several times when young, foolish, and damned poor. CAN NOT, and DO NOT RECOMMEND getting under it. All-too easy for it to topple even off very good jackstands, easier yet to come off of 'expedient' supports.

Get the vehicle to a facility with a proper chassis lift, and/or a wheel dyno where it can be run without risk.

Use some combination of microphones, mirrors, fibre-optic snoopers or cameras. USB 'webcams' are cheap as dirt nowadays anyway, and wall-mirrors from Goodwill at ten bucks and upward can be slid under the vehicle on sheets of cardboard, no great loss if broken.

 

funny enough phoned a old school family garage just now and explained the problem and first thing he said was sounds like propshaft so got it booked in tomorrow to take them out on a drive then get it on the ramp. All I need them to do is confirm what it is then I can go ahead and buy the parts and fix myself.

 

just had an hour with a mechanic great bloke didn't even charge me, we went on a drive and straight away he agreed with the problem and said that is the prop of the gearbox. We then got the car on the ramp had a look under and nothing was really a miss. you could tell that the prop had been off in the past for some reason due to line up markings. He tightened all the prop bolts and all were tight apart from one had a few turns in it and when he did tighten it the nut and bolt moved around slightly suggesting that maybe the coupling has gone. He said if it was his car he would change the coupling I just need to find one now does anyone know if the s type shares the same piece as that is readily available but I cant find an x350 one anywhere. If it is not this has anyone ever heard of the zf box making this odd noise I did a quick search on the bmw forums and found nothing.

 

hmmmm .... sounds like the mechanic deserves a bottle of the finest whiskey delivered at the earliest opportunity

 

I may have been to soon phoned a local auto gearbox specialist guy I have used before who also has a jag and is a big fan and we use the same dealer. He went out for a drive with me tested the gearbox under different loads and ranges and kind of ruled out it being the box. He then got in on 4 posts and ran the car got stethoscope job out and went having a listen to everything. First thing that was noticed was that my rear alloy was bent as nobodies business ones again jaguar didn't mind charging me for balancing instead of telling me there was no point. The second thing was the noise was slight but there and we narrowed it down and the only thing that was making any noises was the centre bearing. He is due to call me back as the place he uses is about 40 miles away and only take the parts not the whole car so the thought is that as long as this wont cost an arm and a leg I will have my tranny serviced with him at the same time. I do like people that share the same boxes working on them means nothing jumps out for them.

so fingers crossed that it wont be to much money as I know have to buy a new rim

 

Switch it with the spare rim (assuming yours are 5 matched).