Engine Noise

[big wheel]

I need help with this engine noise.

It's an 05, 1.9 tdi with only 28,000 on the clock.

It's hard to discribe a noise because it's not a knock or banging noise.

It started 10 days ago and is getting slightly louder every day.

When you pull away (forgot to say it's an auto box) you get a whirring noise like a dry bearing. It doesn't increase with road speed, only with engine speed. If you stop and gently press the throttle you can hear it from tickover up to about 1800 revs, where it stays constant. When you open the bonnet and listen, it sounds like the right hand side of the engine. A few mechanics have listened to it and nobody seems to agree, we have had turbo bearing, but it's not a whine and does not seem that fast. I have had cambelt tensioner and idlers, and the noise transmits to the other end of the engine. It sounds like a dry bearing/ clutch noise. Is there an air/con drive that might make that noise, any ideas would be welcome.

If I can't pin it down, I think I will go for the cambelt tensioner idea to be on the safe side and change them this weekend.

Come on lads, any ideas are better than none. Any idea how much a full belt kit costs and how bad it is to do.

[Phil]

H, I had this problem about 2 weeks ago and i thought the same, cam belt idler roller, BUT i removed the alternator belt and run the car with it off for about 2 mins and the noise had gone, i replaced the alternator and now she is quiet, turns out it was the alternator bearings that were shot.

 

HTH

Phil

[big wheel]

H, I had this problem about 2 weeks ago and i thought the same, cam belt idler roller, BUT i removed the alternator belt and run the car with it off for about 2 mins and the noise had gone, i replaced the alternator and now she is quiet, turns out it was the alternator bearings that were shot.

 

HTH

Phil

 

Well done Phil.

Thanks for the reply, they say sometimes you don't see the wood for the trees.

All these mechanics have been looking for the most expensive repair, not one even said take the belt off and see what happens.

Last year I had the usual Galaxy electrical problems, but that's another story, and they said an Alt' was

[andyfishing]

An easy check for belt problems. along with idler pulley and alternator bearings is to spray the belts lightly with WD40. If the noise disappears then you have narrowed things down. Alternator bearings can sound like the engine is about to self destruct as the resonance can be amplified through the whole engine. However, if you spray the belts and it makes no difference then you have to investigate further.

 

Another culprit can be the water pump - easy way to check is to put a little water wetter in the coolant and see if it decreases (it adds extra lubricant) if it does - time for new water pump.

 

It is a long time (20 years) since I last heard a big end knock on a well maintained diesel.

 

Peace

 

Andy

[chrispb123456]

Hi there

As Phil said slip off the auxilary drive belt, run engine see if noise is still there, suspect alternator bearing/s, auto belt tensioner.

Thats pretty low mileage for the year, although after five years I would consider changing at least the belt. I change mine at 40.000 ml intervals, last change was belt and rollers

[big wheel]

An easy check for belt problems. along with idler pulley and alternator bearings is to spray the belts lightly with WD40. If the noise disappears then you have narrowed things down. Alternator bearings can sound like the engine is about to self destruct as the resonance can be amplified through the whole engine. However, if you spray the belts and it makes no difference then you have to investigate further.

 

Another culprit can be the water pump - easy way to check is to put a little water wetter in the coolant and see if it decreases (it adds extra lubricant) if it does - time for new water pump.

 

It is a long time (20 years) since I last heard a big end knock on a well maintained diesel.

 

Peace

 

Andy

 

Nice one, but how can spraying the belt have anything to do with a bearing on the back of an alternator. Maybe I am loosing the plot, but thanks for the reply anyway. Any idea is better than none.

[big wheel]

Hi there

As Phil said slip off the auxilary drive belt, run engine see if noise is still there, suspect alternator bearing/s, auto belt tensioner.

Thats pretty low mileage for the year, although after five years I would consider changing at least the belt. I change mine at 40.000 ml intervals, last change was belt and rollers

[andyfishing]

Nice one, but how can spraying the belt have anything to do with a bearing on the back of an alternator. Maybe I am loosing the plot, but thanks for the reply anyway. Any idea is better than none.

 

 

Mmm yeah - I meant to say - a worn pulley.

 

Andy

 

P.S. I must have my brain in gear.

[chrispb123456]

Hi again

That price for the belt kit was from my local parts/accessory shop not necessarily the cheapest but convenient for me and that was 18 months ago so may be more now.

If the Alternator bearings are the problem it's cheaper to take it off yourself and take it to a starter/alternator repair shop if you have one near you.

Auxiliary belt and the auto tensioner is also available from factors, iirc about

[Mirez]

I've had my car 5 years now and consider myself really lucky for not having the endless problems some people have, trouble is you only hear of the faulty ones on here, but hopefully there's thousands out there that are relatively trouble free.

 

But as you've just said you are doing regular servicing work. I too have had very little issue with mine but do exactly the same, there seem to be a fair few people who'll just use a car without any servicing at all and then wonder why stuff breaks! :)

[big wheel]

Hi again

That price for the belt kit was from my local parts/accessory shop not necessarily the cheapest but convenient for me and that was 18 months ago so may be more now.

If the Alternator bearings are the problem it's cheaper to take it off yourself and take it to a starter/alternator repair shop if you have one near you.

Auxiliary belt and the auto tensioner is also available from factors, iirc about

[big wheel]

Well lads here's the latest update,

Took the Alt' belt off, ran it, noise still there.

Stripped it down and replaced,cambelt,tensioner,guide pulley,water pump,Aux belt and tensioner.

What was the end result of all this hard work, #######ing noise is still there.

It comes and goes, sometimes it's like a whine, but not like a turbo scream. It's more like a chatter that you get with a slipping belt. I feel better that I know all the belts and pulleys have been changed, but it still miffs me off. So I think the next stage is going to be an Italian tuneup, rag the nuts out of it, and blow all the crap out the turbo. Any more ideas lads, in the meantime I will turn the radio up a bit more.

[chrispb123456]

Hi Frank

Bit of a bummer doing all that and still getting a noise, there were some posts recently about the large intercooler pipe bracket snapping in half under the crankshaft pulley, that gives a rattle chattering noise but I'm sure you would have noticed that today, and you say the noise is coming from the drivebelt end of the engine.

Could the noise be coming from behind engine, ie, intake plate EGR valve area?

[big wheel]

Hi Chris,

No mate, wrong end.

If you stick your head under the bonnet it sounds like the flywheel end, but when you drive it sounds like a drive belt idler, so you presume it's that end. I have had mechanic mates listen to it and it's been things like,turbo bearings,fuel pump on the end of the camshaft, even planet wheels in the gearbox. The most popular one was cam or aux belt tensioners, guide pulley or water pump and the sound resonates through the engine. Well they have all been done now,so it's back to the expensive bits. If you can remember back a thousand year when cars where fun, it's the sound a spigot bush or thrust bearing would make.

[tim-spam]

Alternator pulley?

[chrispb123456]

Hi Frank

Running out of ideas now, one of your mechanic friends mentioned about the fuel pump making the noise, now this is a long shot but worth having a look.

The fuel pump is also the vacuum pump which supplies the brake servo etc, have a look at the pipes around the back of the pump/fuel filter area for chaffing/splits, you can get some strange noises through air pressure/vacuum leaks, whistling/whirring, more so if it's nearer the pump

[big wheel]

Alternator pulley?

 

Why do you say that, when I have run it with the belt off and it's still there ?