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As I started the car this morning it sounded awful!

It was as if the thing was about to expire; horribly rough and didn't sound as if it was the tappets (like the old pertol 8v cars would do) but certainly more deep seated. Was loud enough for me to turn it off and try again, as was still noisy for a few seconds.

It had been stood for about 10 hours. Its always been a super smooth quiet engine so this was a suprise and a shock![:(] Never done anything like this before.

Its only done 32000 miles and had the oil changed every 5k with Longlife...though have notice sometimes when starting from cold it lets out a blue black cloud-only noticeable when I park next to the fence at home so the "cloud" is blown past the front of the car!

Do any other of you derv drivers, esp 150PD pilots had the car sould like its a 250000 mile taxi when starting? I'll be a little dissapointed if its the start of engine wear after the tlc its recieved over the time i've owened it.
 

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Cold weather seems to make my car sound like a complete bomber.. I believe its pretty normal on the TDI's.

If the temp is around 3 centigrade or below its very loud - and when it was into minus figures it almost didn't want to start. Yet as soon as the temp crawls back up, the car starts on the first turn of the key without any extra noise and fuss.

Don't worry - i'm pretty sure its normal :)
 

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Yup just a couple of times when its been cold and left alone for day or so its started like nothing was bolted together. Only the first couple of seconds though and its was off the races as normal.

Mine had 46k but my mates got a 115bhp TDI and his is the same and his has 106k so its nothing to worry about.

Joe
 

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I get something similar every now and again, only when it's very cold though and clears after say 2-3 seconds. I've also noticed it hunts a little i.e. the rev-counter needle drops every second and appears to lose say 50rpm for a few mins.

Does the smoke stink on the first puff?? can't really describe it, very nasty acidic, burnt rubber kind of whiff.
 

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Mine sounds noisier when its been left for a few days but the noise disappears within a few seconds. Our petrol 1.6 used to do something similar make a 'clack-clack' noise after start up if its was left unused for a while - I figure this is the tappets pressurising with oil. I'm guessing they 'loose' oil when its been sitting around.
 

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Mine is on 85k now, starts first time, but does sound noiser then usual this time of the year, soon quietens down though, plus it's due a service.
 

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Indeed. After hearing how much an oil change quietened down Joe's Anni, i'm going to do an interim oil change on mine over the holiday break seeing as its such a piece of cake on these TDI's - and then give it the full service treatment when it hits its service mileage in a few months time.
 

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Is the temp sender easy to change?
Yes, pull plastic clip take old one out - quickly put new one in to stop too much coolant coming out - secure with clip - swop plug to new sender - throw old one away[;)]

Worth disconnecting the battery to clear the memory and faults, runs much better now (not as fast 'cos it not over-fueling any more....[:$])
 

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I'm off to VW at lunch to get oil, filter, sump nut & washer so might pick up one of those then depending on the price. Can't do any harm to change mine if its cheap and a quick job :)
 

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Make sure you get the seal with it.

Is yours throwing errors too? I wouldn't bother changing it unless your getting fault codes.
 

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The parts guy at VW couldn't find it on the system anyway so I didn't bother - just got the service bits I needed. Amusing comment from him though...

"Is the TDI 4 cylinder or 5 cylinder.." - errr.....
 

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As I started the car this morning it sounded awful!

It was as if the thing was about to expire; horribly rough and didn't sound as if it was the tappets (like the old pertol 8v cars would do) but certainly more deep seated. Was loud enough for me to turn it off and try again, as was still noisy for a few seconds.

It had been stood for about 10 hours. Its always been a super smooth quiet engine so this was a suprise and a shock![:(] Never done anything like this before.

Its only done 32000 miles and had the oil changed every 5k with Longlife...though have notice sometimes when starting from cold it lets out a blue black cloud-only noticeable when I park next to the fence at home so the "cloud" is blown past the front of the car!

Do any other of you derv drivers, esp 150PD pilots had the car sould like its a 250000 mile taxi when starting? I'll be a little dissapointed if its the start of engine wear after the tlc its recieved over the time i've owened it.
Hi mate

I'm glad in a way this happens to other people too cause I thought my engine was developing problems. Mine sounds terrible for a few moments after starting, more than a typical knock, and I also get a cloud of smoke sometimes. Once the ECM has detected the temp etc and the fuelling adjusted it's fine though. I noticed you've had a remap too. I've had a Revo tune on mine, so from a very cold start, which is when this happens, there's probably a bit too much fuel going in initially.

The cloud of smoke was starting to look very blue as well, but not all the time. It looks to me like a mixture of fuel, and a small amount of oil thats leaked through the turbo seals. I am very religious on letting it tick over for a few moments after any journey though which should help prolong the life of the power snail.

Mines done 55000 (30000 when purchased), and I've had to have a new turbo and cat cause it failed and spewed loads of oil down the exhaust. I insisted on a cat change, but the silencers were left alone. For that reason, mine may smoke a little more anyway.

You can rest assured you're normal!

[:D]
 

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Mine's alot better now I've got round to changing the temp sender - much quieter.
Richard,

All I read that you write, I agree with but in this case I cannot understand how a new temp sensor makes a difference on the noise made on a cold start or are you refering to the period just after the tappets have quietened down ? The period up to 90degs where there maybe more accurate control of the cold fuelling giving rise to more a civilised warm up ?

As for the tappet noise, as long it goes in 5 to 10 seconds, it's nothing to worry about, just don't rev the engine as if the tappets are dry the turbo will be as well.
 

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Basically because the temp sender was telling the ECU that the engine is very cold, instead of adjusting the fuelling after start up to match the real temp it simply dumped fuel in making the engine louder (that diesel knock that we all love so much[;)]) than it should've been for the first few minutes.
I know about the tappets and like most here am quite religous about giving the oil time to work it's way round.

The other symptom I had was that when I did a warm start the engine would rev it's knack*rs off without touching the throttle for the same reason. Hence my concern about damage to turbo etc.
 
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