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Discussion Starter · #1 ·
If your GT TDi has an 'odd' driving characteristic (hesitation under light load) and maybe feels a bit lackluster - this may be your solution (I've had it sorted at VW - under warranty)

PROBLEM;

Vacuum loss in the vacuum system through a faulty membrane in
the vacuum adjusters of the vacuum system (EGR cooler bypass
flap, EGR valve and turbo charger). [Basically a fancy N75 valve!]

Sporadic malfunction in the solenoid valve block.

SOLUTION;

Various improvement measures in the vacuum system.

Optimised solenoid valve block, identified by
the production date >> 28/04 on the barcode
label of the solenoid valve block.

IDENTIFIED BATCH

The Chassis numbers affected
WVG ZZZ 1TZ 5W0 29686 => WVW ZZZ 1KZ 5B0 36722 =>
WVW ZZZ 1KZ 5P0 26710 => WVW ZZZ 1KZ 5W0 62000

So, to recap, improved valve blocks are fitted from WVW ZZZ 1KZ 5W0 62000 onwards, hence if your chassis number is earlier than this it possibly has a valve block from the faulty batch.

To check if it is, look at the barcode sticker on the valve block
and if its earlier than 28/04 (week/year) then its probably at fault.

_______________________________________________________________________________

Big thanks go to a very helpful VW technician who knows more about VW's than perhaps VW do - and who shall remain nameless.......but I will echo your gratitude to him.

If you think you have the problem and are in the identified range, have a chat with your dealer about having it sorted...........and while your at it - ask about the dual-mass flywheel recall / replacement too.
 

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I had mine in last Tuesday for this fault, which they could not find on a test drive. No mention of this tech note though, is it an official VW release do you know?

Also, where can I find the 'Valve Block' ?

Cheers
 

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Thanks Foxy,

When you say hesitatation, is this the problem of what feels like under-fuelling between 2 and 2.5 k on partial throttle? The car feels like it is pulling back for a very brief moment and then all is well.
 

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Discussion Starter · #6 ·
Thanks Foxy,

When you say hesitatation, is this the problem of what feels like under-fuelling between 2 and 2.5 k on partial throttle? The car feels like it is pulling back for a very brief moment and then all is well.
This is EXACTLY the fault........it was very pronounced yet sporradic.

The dealer couldn't replicate the symptoms on many occasions either but couldn't refuse to do the replacement as there's a technical bulletin for it.

YES - this is a VW technical bulletin.
 

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Thats brilliant. Although not a major problem the car really does not feel right when it does it. I am glad there is a technician somewhere with the technical competence to be able to resolve these problems. Looks like I am going to have to get it booked in and get it sorted then.

Thanks agian for letting us know
 

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Foxy, that is brilliant, just the info i need.

I mentioned before that the tech at my dealer refused to acknowledge this fault about 9months ago. Given that i picked my car up on 30/4/04 it is most certainly in the batch.

Thanks again
 

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Discussion Starter · #10 ·
The Valve Block *may not* have an ID date on it - however, it is located on the bulkhead (firewall) right up near the bonnet level, to the right of centre of the car (when looking from the front of the car) - perhaps just above the ABS pump. It is a rectangular box with a rubber connector having 6 or 8 rubber hoses connected to it.

My tech asked me if mine had a coloured pencil "X" marked on it (maybe yellow) - as he said that probably signified the MODIFIED unit.......mine HAD the "X" but was replaced.
 

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Oh Bum !

I was all ready to descend on my dealer with this info - but my chassis code is later than those mentioned and the valve block does not have any date or barcode sticker on it. May try anyway and see what they say.
 

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which part of the chassis code do you use? just the last five digits or all of it? The reason I ask is that my chassis is 4B0 68315. So the last five digits are later than those listed but the 4B0 is confusing me since it doesnt fit with those given.
 

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Two dealers I've spoken to about this haven't got a clue what I'm going on about!

They reckon they've been on to VW Tech and they haven't got the bulletin referred to. Does it have a number I could quote them Foxy?

My car's in the affected chassis number range, and it hesitates every now and again (though doesn't feel slow in the slightest! [:)]) as described so ideally would want to get it sorted before the 60k mark...

I've just gone over 40k now, and apart from this little issue, I've got no other problems with the car - Fab! (On my third windscreen though! - guess I'm just unlucky!)
 

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Sorry but they are B/Sing you. My car has been in VW Guildford all week and they are aware of the technical bulletin - and my car was registered in May 05. Just mention the problems with the car as described by Foxy and they should find it. OK, so my car has to go back in for the work but atleast VW know abt it.
 

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which part of the chassis code do you use? just the last five digits or all of it? The reason I ask is that my chassis is 4B0 68315. So the last five digits are later than those listed but the 4B0 is confusing me since it doesnt fit with those given.
Can anyone help with this?
 

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Discussion Starter · #17 ·
which part of the chassis code do you use? just the last five digits or all of it? The reason I ask is that my chassis is 4B0 68315. So the last five digits are later than those listed but the 4B0 is confusing me since it doesnt fit with those given.
Can anyone help with this?
I think that 4B0 is an earlier chassis nuimber........what was your date of manufacture?

I think that if you've got the symptoms, VW will try the repair
 

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Thats my thinking too. I think the 04 must be the build year. I dont know if my car does it or not. It seems that now im looking for it, I can sometimes feel it but dont know if its pyschosomatic now!! I'll assume for now that because mine isnt listed in the model numbers that it isnt an issue
 
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