Soot buildup on top of engine

[Disco4TT3]

I've noticed some soot build up on the very top of my engine (3L TDV6):

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Before I go pulling it apart, I'd love to know what parts I might need to order. Are there some seals/o-rings here that might need to be replaced?

Anyone got any suggestions?

I had a look at the parts catalogue here but can't seem to find that section:
Discovery 4 2010 - 2016 (l319) / Intercooler/air Ducts And Hoses (3.0 V6 Diesel)((v)fromaa000001) | Jaguar Land Rover Classic Parts (https://parts.jaguarlandroverclassic.com/parts/index/part/id/22.52662.52775.43443/brand/land-rover/)

[DiscoJeffster]

Could be a split somewhere. That's the most common reason for that. Manifold, throttle body etc

[Disco4TT3]

hmm ok - no errors or loss of power even when I boot it, which I thought would come from a split.

But thanks - will pull apart and try to find the source.

[DiscoJeffster]

Remove the engine plastic cover. Place sheets of white paper on the top of the engine. Replace the cover. Take it for a drive. Remove cover and check the paper for the source.

[Disco4TT3]

Thanks for the suggestion DiscoJeffster.

Unfortunately the paper test was a little inconclusive - but visual check seemed to show it leaking from the where the egr pipes connect to the TB and where the TB connects to the manifolds. So I picked up some new seals and egr pipe clips to fit - parts LR008353, 1316152, 1311338

However today when I went to fit them, I noticed this pipe has been snapped/cracked before and taped together with electrical tape - wasn't me I swear - I would've used gaffa tape at least :)

LR015456

The web tells me it's a turbo pipe / branch pipe / oil pipe - anyone know what it actually does and what happens if it leaks or is not connected?

It seems to go down to the primary turbo but don't understand why it connects to the Throttle body elbow. As its a Saturday, I won't be able to get a replacement today.

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[DazzaTD5]

re you broken pipe, you can use some fuel injection hose of the correct diameter that will slip over the cracked pipe.

The other goo, i have hi-lighted your pic, the red circle, the black goo often comes from the seal leaking or the front of the throttle body not fitted correctly, which is the hi-lighted orange circle.

After that I would give it a good degrease and clean. The only sensor you need to cover with plastic is the oil pressure sensor, front of passenger side manifold with a green plug, only because it can get some water in it and cause the oil light to stay on until its dried out.

[Disco4TT3]

ah good idea - will go find some hose. Gaffa'd on for now and not throwing faults, so can head to the shops.

I bought new seals anyway, so will replace and check fitment.

thanks Daz.

[Disco4TT3]

Ok repaired with a new hose today:
Just a moment... (http://www.repco.com.au/parts-service/intake-exhaust/car-vacuum-tubes/saas-silicone-vacuum-hose-8mm-id-x-3m-black-ssvh38mm/p/A5499215)

The hard plastic part of the original hose is extremely brittle.

I did some RTFM over the weekend and found the below in the WSM:

"The compressor end of the turbocharger has two hose connections; the central connection provides the clean air supply from the air filter. The second connection on the outside of the turbocharger housing allows the connection from the turbocharger to the charge air cooler."

So, I assume this pipe is the "clean air supply from the air filter", since it's connected to the TB elbow. Interestingly, the car seems to perform a lot better since repaired - could possibly be my imagination! But I was recently complaining about the fuel economy I got on a round-trip from Melbourne to Sydney where I averaged around 13L on the way up and 12L on the way back - I recall getting <9 last time. Time will tell if it has improved efficiency.

I found this description of the part here:
LR084276 Land Rover Discovery 4 (2010-2016) [3.0 Diesel 24V DOHC TC] PiPE - TURBO BOOST (https://landrover.scuderiacarparts.com/part/1085352/landrover/lr084276/pipe-turbo-boost.html#spec)

"This component plays a critical role in the engine air intake system, facilitating the efficient flow of air to the intercooler, which in turn improves overall engine performance and fuel efficiency..."


It sounds a little AI generated :) But if true, I'd love to know how this pipe plays a role.

[Graeme]

I suspect that the efficiency part refers to the use of an intercooler.

[Disco4TT3]

Hmmm.. I've re-read the "Turbocharger - System Operation and Component Description" section of the WSM and it still doesn't shed any light for me.

Anyway, I removed the TB and gave it a decent clean today. The seals were rock hard, so I replaced all 3 with newbies. We shall see if that solves the leakage issue.

The MAP sensor and its hole were almost completely blocked and the amount of crap in the manifolds and TB was sickening. Whoever thought EGR was a good idea...

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[Disco4TT3]

Forgot to mention, I just received some of those aluminium inlet manifolds from China - $102 + delivery each. They look pretty good.

I also got a replacement TB for $130 + delivery - this looks ok but has a plastic 'flap' whereas the original seems to be brass or some sort of metal. The rest of it looks the same as original.

I'm still planning that job as I've seen how challenging / time consuming it is.