Engine judder on cold start up

[Nathan27]

Hi all, (firstly sorry for the long message in advance)

I've owned my first ever diesel and transporter T6 2015 (101,000 miles) since June this year and I've got a juddering issue when starting the van up especially after leaving overnight but now even after 4 hours.

Originally when I first bought the van it didn't occur however after a month of ownership I would notice a small judder if not driven for a few days. Now every morning for around 1 minute the engine judders as if there is not enough fuel getting to the engine or as if some form of timing is out. It feels as if week by week the judder is becoming more noticeable.

I have taken it to VW and a VW specialist, they both said they could not find a problem after diagnosing and having a full service. The VW specialist that had it recently for a couple of days said they didn't notice anything and "could've just needed a service". They completed the service and also increased the amount of fuel injected on start up. I got back in the van next morning and the juddering continued and has been made worse with the increased fuel on startup.

The following day I got a new battery as apparently it was "knackered" according to the battery specialist so a new one was put in and immediately the van felt much smoother, I thought this would resolve the issue. However again the following morning the judder was back and the van no longer felt as smooth.

Since the juddering has gotten worse I have also experienced other issues alongside the juddering: longer cranking issues but only around 5 times, also once the judder has stopped (on first start-up after 1 minute) if the heating is put on it suddenly starts to judder again as if it wants to stall. Another thing is higher held revs on idle again which has only happened a few times once driven. Also very rarely I have noticed slight juddering when pulling away in first or reversing when the van is still cold which could be the dual mass flywheel but I am unsure if this is connected to the juddering when starting the van. On a couple of occasions a ticking noise when first started up has occured alongside the juddering but once warm has gone away.

Once the van is warm the engine seems fine with no juddering and if left for a couple of hours then started up again when cold it seems fine with no issues, it only seems to be around 4 hours plus, especially overnight.

I then called up VW again and another VW specialist and have concluded that they have all said without a light on the dashboard they basically can't do anything for me (due to their being no warning lights to diagnose). I'm at the stage now where I don't know whether to keep spending money on all the possible things it could be (and potentially not resolve the issue) or leave it until it gets really bad that a light comes on.

Sorry for the long message, thank you in advance and any help/guidance would be much appreciated as I really don't know where to go next.

Thanks

 

[bluezie]

Could be all sorts of things, but a compression test would be a start, if a single cylinder mis-fire, it could have a bent con rod from hydrolocking, could be low compression all round due to bore wear. (CFCA Biturbo 180 engine?) Also getting it on proper diagnostics and reading the live activity in the measuring blocks may give some clues, could be erratic fuel rail pressure, a bad injector/s, bad readings from a sensor due to wiring faults etc..
But without access to this type of workshop gear, it's all a speculative guess. If the so-called VW specialist has said they need a dashboard light to be able to diagnose this, they are not a specialist, they are very amateur! VW themselves just use guided fault finding on their diagnostics, then either walk away, or fire the parts cannon at it ££££££!

 

[Nathan27]

Thanks for your response, much appreciated.

The engine is 102 not 180.

So does the compression test include a fuel compression test or would that be something separate?

To get proper diagnosis done, I take it the best place is still a VW specialist?

 

[Dav-Tec]

There's various tests that can be done to check the injectors are in spec etc. I wouldn't let it get worse as you don't know what damage could be caused

 

[Dellmassive]

My first thought was low compression.... (Worn engine, does it use a lot of oil?)

What van, engine is it?

But a DMF is also possible.

But need to see or hear the engine to get more info.


Can you get a video clip of it.?

Drop that on YouTube and post a link here.... Or just a link to it on your online photo album.

 

[B.different]

Could it be possible that timing is out slightly with a worn tensioner?

 

[Nathan27]

My first thought was low compression.... (Worn engine, does it use a lot of oil?)

What van, engine is it?

But a DMF is also possible.

But need to see or hear the engine to get more info.


Can you get a video clip of it.?

Drop that on YouTube and post a link here.... Or just a link to it on your online photo album.

VW T6 2.0 TDI 102, 101,000 miles and not sure regarding the amount of oil it uses.

I can post a clip but it's really hard to hear the juddering. But I'll try post a couple of links in here.

Thanks

 

[Nathan27]

Could it be possible that timing is out slightly with a worn tensioner?

Previously this occured in 2018 but surely is unlikely to occur again...

 

[Nathan27]

Here's a more recent video taken after the full service:

 

[B.different]

Its 6 years old so be worth a check for the sake of an hours labour. It's possible, I had a new engine fitted and whilst it was being run up to temp the new aux belt failed.