Noisy TDI

[Wortho]

Hello to everyone, I have an intermitant noise from my engine ,300tdi, it's sort of like the engine is rumbling as the revs get higher(from 2,500) and also when the revs are falling at gear changes. I have noticed that if it's not a cold day it does'nt do it but it does when its cold especially at night. Could this have somthing to do with the fuel being to cold as i've heard that some diesels have heaters in the tank to pre warm the fuel or could it be something more evil is lurking in my engine. This is my first diesel so i'm not that clued up on them and never had one at winter before. Just had oil change Penrite hpr15, engine has 260k on the clock, manual 1995 tdi disco, 40k left on timing belt, new water pump.
Any ideas at what to look at much appreciated.

[DEFENDERZOOK]

<span style="color:blue">what do you mean by rumbling.....

is it something you hear or feel or both......?


was it doing it before you changed the oil...?</span>

[Wortho]

Something i'm hearing(that sounds good) and yes it was doing it before the oil change but only for the last 3wks, i thought it was because the oil was due to be changed but apparently its not. Changed the oil two days ago have done about 280k's since then. The funny thing is that it's intermitant and usually only on a cold day or night.

[Pavo]

Interesting - my 1997 build 300Tdi sounds very 'tappety' in winter on cold mornings. On mine, the sound is like the valve clearances need adjusting or one of the little valve caps is cracked, hence the the tappety sound. (But clearances are fine, it's just what it sounds like). But never does it in warmer weather. Funny thing is, I seem to hear it even once the engine is warmed up and driving on a freeway. But haven't heard it since last winter, so I might be forgetting some details.

Has done it every winter, I think. I once considered a thinner oil than the 15W/40 just for winter - thought of 10W/40 MAgnatec - but I never bothered. I figured everyone uses 15W in England and it's freezing there.

Interested to hear if other have same thing.

Oh, and it's got 120,000kms and in excellent running order.

[Wortho]

Good to know it's not just mine that makes a wierd noise when the wheather is cold and mine is running great appart from that and then only when it's cold(wheather ,not engine). I was starting to get really worried.

[one_iota]

All that I can add is that a mate with a Td5 said to me that my Tdi sounded really good :?:

[jase]

only "rumbling" noises I ever heard from Tdi's is front pully/waterpump/tensioner bearings on the way out
these noises normally change (sometimes get better sometimes worse) with temp also
Jase
PS also check (but not normally temp related) harmonic balancer is tight 8O

[JohnM]

Is the "rumble more prevelent on startup when is cold....Is it a more like a metallic noise?

Remove your fan belt/serpentine belt, then start her up and see if the noise is gone. Hopefully the noise will have gone away and this will at least point you to the belt or pulleys, and hopefully not anything internal. I have had a few belts that seem to get old and become metallic sounding when cold, once they warm it goes away.

[NOZ]

I know it sounds odd but as said above, check your pullies and belts. I had a tappet sound had the belts replaced and it went away.

[Wortho]

The water pump went about 1000ks ago and had everything checked and a new belt then, seems to have nothing to do with engine temp just outside air temp which i know sounds wierd, still i'll recheck the pulleys and belt over the weekend and see if theres anything there. Don't think it's to serious a problem i'm just bloody curious as to what it is???.

[abaddonxi]

Turbo?

Cheers
Simon

[Wortho]

Seem to have solved the problem. Checked everything even cleaned the intercooler then finally changed the fuel filter and the noise is gone.
So if anyone has any wierd intermitant noise from there tdi when it's a cold day or night check your fuel filter, weird i know but that did the trick.

[british4wd]

remove the drive belt and run the engine, if the noise it not there it has to be one of alternator, water pump, power steering pump or any of the idller pulleys.
If noise is still there with the belt off have a listen to the brake vacuuum pump, these get very noisy when on their last legs.

Alan Howard