Another coolant leak! Photos within. 3.0Tdi Q7

[davidjessop]

Hello. IÂ’ve just had a little bit of a trawl through the many threads about coolant loss.
Our 2016 3.0 has been using around 1l per 500 miles for the last couple of months. Undertray removal shows a clear path of the coolant but nothing visible without significant disassembly.
From the photographs does anyone recognise the pathway and want to prepare me for what’s coming! 🤣
Thanks guys, David.

[davidjessop]

Photos will follow shortly.

[Nemo78]

As you e probably seem in the thread a common issue on the car - not sure what the cost is to fix out of warranty but you could probably argue it’s a know issue.

Not sure if there was a TSB at all for it?

[wardienet]

I had a look on my paperwork it just says “new coolant solenoid value” and as I had the extended warranty that covered it, minus excess. But my dealer told me because most of it is a load of labour to dismantle/assemble the engine to get to it, it would have cost retail just short of £2k. Eek.


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[davidjessop]

Crikey. I can see it’s going to be no mean feat to find. The car actually went in for a dealer service on Friday and the leak was picked up. £850 quoted to assess.

The car had been without fault pre service - yet didn’t make it home before throwing warnings and and has just been recovered about an hour ago. Looks like it’s no longer charging. You couldn’t make it up!

Thanks for the replies - I’ll figure out the photo’s tomorrow.

[wardienet]

Crikey. I can see it’s going to be no mean feat to find. The car actually went in for a dealer service on Friday and the leak was picked up. £850 quoted to assess.

The car had been without fault pre service - yet didn’t make it home before throwing warnings and and has just been recovered about an hour ago. Looks like it’s no longer charging. You couldn’t make it up!

Thanks for the replies - I’ll figure out the photo’s tomorrow.

Use a different dealer or specialist independent? They shouldn’t be quoting £850 to diagnose a fault you will pay to fix surely? Will that be offset against the repair? Ouch. FYI my dealer made a mistake when reassembling the engine, they just forgot to attach one of the leads for the cylinder heat plugs properly. Engine fault yellow light etc. They diagnosed and fixed it same day and I got some compo for the hassle as they were hugely apologetic.


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[davidjessop]

I think the issue is that to accurately diagnose the disassembly process is pretty time heavy. Front off, and a fairly major strip down to below the intake manifolds. No going back at that point is there?!

[wardienet]

I think the issue is that to accurately diagnose the disassembly process is pretty time heavy. Front off, and a fairly major strip down to below the intake manifolds. No going back at that point is there?!

My dealer didn’t need to do that to diagnose the problem... very likely to be the known issue.


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[andyhud007]

David

This is a well known issue. Parts are circa £150/200 to buy, its the 3 hours taking fuel lines/pipes off the top of the engine to replace the Coolant Solenoid. That is the culprit. Nothing more than "poor design" and it wears out over time. Needs to be replaced with a new version and put everything back in reverse

Took me 5 hours....

This is the culprit part.. the valve that "slowly" leaks.

IMG_20200215_115340_1.jpg


and this is the effort to get to it.. its right down the middle. but its all do-able from the top down.

IMG_20200215_130324_4.jpg

The hardest bit of all is putting the intake manifold valves back on.. One screw is just a nightmare to get your hands too...

The valve itself is about £80, but you need to replace seals etc and screws so it bumps up to the £150+ mark in parts. but the dealer is right, the cost is all labour...

The TSB (Technical Service Bulletin) is 2047044/8

Andy

[andyhud007]

Nah, not true. You can see the leak by just taking the engine cover off and a really bright torch shining into a very specific place.. you can see the coolant dripping out...