Hi all

Ive been following various people with this same fault but the ultimate answer is always missing so decided to post my own list all in one place.I have been chasing this fault for 3 months so doing my best to stick to the facts .

2005 t5 1.9 tdi 160k

The problems and tests are as follows

header tank pressurising and blowing out the pipe underneath ( proved with ultraviolet additive) and a poo bag tied under it!

changed the header tank and cap

inspected the water pump

uses as much water round town as on a 500 mile trip

oil ok no scum

pressure tested the cooling system

new stat from tps

tried steel seal

2 goes at sniff testing the system at different temps over the last few months and then as a final go i sat for ten minutes with the revs at 4k without a bubble coming back up the sniffer vessel,nothing until you back off the revs and then hay presto bubbles and a reaction with the chemical to say there is exhaust gasses after all.

the question is can this be anything else other than the head gasket ie the ERG valve cooler ive seen mentioned?

can anyone explain why the pressure increases as you come off throttle?

am i in denial ????????????????????????????????????

 

steel seal is a complete waste of time, as is all its ilk.

If you havent got an egr cooler its head gasket or issues with the head becoming porous or cracking. If you have got an egr cooler, bypass the cooling and see if anything changes.

But its fairly likely its head gasket.

Failures can occur between the water jacket and the piston chambers, very commonly in fact, hence no oil mixing issues.

 

Same symptoms as mine. It's not a hard job to do on your drive. All you'll need is gaskets, new head bolts and turbo oil feed line. All available from tps or dark side developments. Head skim is between £150-£200. Parts around £150 and labour around £200.
Bit of a nightmare this side of Christmas but good luck!

 

thanks chaps

ive been thinking if it only pressurises the cooling system as you come off throttle that would be as the EGR valve goes to recirculate the exhaust gases would it not? ive driven this van to the alps and back with this problem starting the day before we set off to do the mega avalanche,only used 1lt of water in 2000 miles because the throttle was constant, surely that points away from head gasket, either way its £600 plus but as long as its spent on the right bits LOL: . next test is bypass the egr cooler if it has one.

thanks again

 

Not sure if your van will have one, you should check.

tbh with symptoms like this on vag tdi, its usually head gasket.

When having HG done youre often looking at full timing belt service, water pump usually, and possibly top end refurb and glowplugs.

Think on all the worthwhile jobs to get done while the labours combined.

Depending what and where might be doable around £600

 

Unless like me I done bigger turbo and injectors. Honest wife they need to be overhauledLOL:

 

Well yes, theres always an opportune upgrade if youre so minded

I had to have the turbo removed and checked on my BNZ, so with some advice the ECU can handle it until a remap I fitted a BPC turbo.

 

BTW if that sounds simple its a 2.5 4MO, so propshaft, DPF, subframe all had to come off just to get to it to prove there was a bad oil leak.

 

Hi have a 2007 transporter BNZ T5 2.5cc 229000 ml clock up ,have white greyish smoke coming from the exaust any feedback would be appreciated