M47 Diesel Engine Whine / Whistle On The Overun

[Jules]

These posts are what I saved from owners back in 2004 when all the warranty claims were pouring in.

Service managers gave up on the problem:SHOCKED:

Well we are not going to give up are we? Good reading:

taylorm 06-09-2004 18:34
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75 CDT engine whine

From new a low engine whine comes and goes; stopping the engine and re-starting sometimes gets rid off it, but sooner or later it comes back. When there, bonnet up it is easily heard when engine running, in cabin it is more obvious when not under acceleration (I did think it was only on trailing throttle, but that is not in fact so once you put bonnet up). Dealer say they can't trace it and "wait till something breaks", but as it is nearly three years old it is getting silly! And it is starting to drive me mad...They did say they had had no other similar problem, but now say a new CDT has same problem. Car is 75 CDT Club tourer. It is "logged" with Longbridge, but they have no suggestions it seems. Any ideas?

cjard 06-09-2004 19:12
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does the noise vary in loudness or pitch when the engine revs change? what about inclines? does pointing up or down hill or parked on the side, alter the noise? is it more or les snoticeable when the engine labours, or when the vehicle is in motion? when you press the clutch, does it come or go? does the gear that the car is in seem to make a difference? are all fluid levels correct (power steering pumps typically whine like this)

Dr Dave 06-09-2004 20:45
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There have been other posts about a whiney 75 Diesel here previously - I can't recall the outcome.


I think the dealer was perplexed there aswell.

jtcoops 06-09-2004 21:44
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My 04 CDTi ZT is doing the same damn thing, and Rubicor has been battling for some time with his dealer to resolve the problem with his 75. To be honest, he's had better response than me, my dealer has pretty much given up.

Mines has been back twice. First time they claimed they'd fixed it but it came back worse. When they eventually took it back in, it had become quieter. After a week of tinkering, they sent it back saying its a characteristic of the engine, and that MGR in Longbridge have confirmed this, and also by the way they had started up three other cars and found the same noise, proving that its a characteristic. Also the whine was back with avengence, and still annoys me.

Of course this is all nonsense, as the demo model I test drove had no such whine, and other owners on here have no similar issues.

Rubicor has had a new turbo, fuel return pipe, and the belts all loosened and refitted and his car is back in this week I think for more investigation.

If the three of us keep sending our respective cars back in, odds are one of the dealers will find out what is causing it and we can post the fix for others.

taylorm 07-09-2004 08:17
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The key element of the noise is that it comes and goes - one time you start up, and it is there, another time you start and it is not. So it clearly is a fault, rather than simply typical of the engine. In the cabin it is somewhat masked by other noise, so you hear it more on a trailing throttle, but bonnet up it is clearly there all the time (related a bit to engine speed perhaps, so slightly quieter at idle). Naturally, once aware of it, you notice it much more and it is gradually driving me crazy. Someone must know a solution - please!

jtcoops 07-09-2004 11:16
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I find it happens between 1,000 and 2,000 revs only, and is most noticeable when doing the slow traffic bit. You can hear the noise disengage as the rev counter drops just below 1,000.

Is yours the same?

taylorm 07-09-2004 14:57
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I think that is how it sounds in the cabin - but try parking up and lifting the bonnet - as revs pick up it will too, but it is there (I reckon) all the time - at very low revs less so, and at higher revs (or accelerating) more drowned out.

taylorm 08-09-2004 08:50
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Hmm....seems like this is a known problem (ie several of us have it, so god knows how many others) with no solution. Ironically, presumably courtesy of BMW (now, surely they would tell us....not....)

cosb6 08-09-2004 08:56
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Where abouts is the sound actually coming from?

taylorm 08-09-2004 11:31
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Garage can't work that out even with a stethoscope! "The engine"! Sounds a bit like a belt slipping very slightly, or a moving part rubbing against something else, but can find no evidence of either. Thats why they pursuaded me to wait when it first started, as they said that they would be able to tell when it got worse - but it just keeps coming and going with no sign of getting worse (or permanently better!).

jtcoops 08-09-2004 12:29
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The thing that gets me is that I know its not something that every CDTI suffers - the demo car I had for 3 days for test driving didnt have it, so my car shouldnt.

My dealer won't entertain any more investigation saying its a characteristic of the car. Now if I didn't know better that would be enough to prompt me to sell the car on and never buy a CDTi from Rover again.

They really don't help themselves.

Dr Dave 08-09-2004 12:44
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Yes.....not a very good attitude is it?

Rover_ron 09-09-2004 18:32
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This is not caused by the EGR solenoid valve is it?
(Assuming the 75 has one!)

The one on my 45 makes a faint whine or buzz audible from in the car which comes and goes depending upon how much exhaust gas the ecu decides to recirculate.

A pic of it is attached to a reply I posted in

"220 SDI Turbo Problems"

Knowing what it is means I don't worry about it!

albion 25-07-2005 14:41
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Hi,

And is the problem been solved?I think I got the same whine in my engine.
She is just 4 weeks old!!!

Thx for the feedback,
Albion

julianviolin ME !!! 07-02-2006 21:54
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75 CDTi Engine whine on the over run SAGA!

Well Hello from a new member! I've had 3 x 04 Reg CDTi's now all with the darn whine that my Local Rover dealer can't get to the bottom of. One technician put his stethascope all round the engine and the loudest point I had to agree with him was coming from the Drivers side engine mounting!!! It's called a Hydromount which means the rubber is fluid filled(how could that make a noise of about 1 Khz. So I thought right go home - raise engine on jack with plank under sump disconnect bolts & links from the hydromount....... naa Noise still the same, so I don't believe its that. Sounds like a reed non return valve type noise to me. The process of elimination continues.....