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[Nomisb]

Afternoon All,

Not sure if anyone can help - this makes a refreshing change from working on the series land rover but.... Land Rover Range Rover TDV8 3.6 L322 (2007)

Getting black smoke on hard acceleration. Engine needs to be warm. It won't smoke unless it's actually moving ( so revving it on the drive doesn't cause it). No engine lights and no codes or warnings.

Black smoke says to me fuel

I've taken the top two turbo hoses off and no cracks or splits. I've not looked at the two bottom ones.

Smoke out of BOTH sides of the exhaust - I'm not 100% sure what the layout of the single back box is so I don't know if the exhaust gasses are mixed or if it's sided?

If it's not the hoses what else should I be looking at?

Any help gratefully received!

[diffwhine]

Any fault codes? Usually anything emission-related will trigger a fault code, but not necessarily the MIL light (depends on market).
Black smoke can also be caused by lack of air rather than excess fuel, so make sure all the usual suspects are in good order - air filter, hoses etc.
The engine management system should not let it over fuel as any irregularities between throttle demand and air flow will cause it to take action to stop this happening. That's when you get limp home modes, power loss etc. Often its just the engine trying to save / help itself. Some engines - the old TD5 being a classic example, can have major problems with air flow sensing which doesn't show as a fault code. You can only see it by real time monitoring. You might have an air flow sensing fault.
First check is to find a friendly garage who can do a fault code scan for you. As this is emission's related, any standard OBD scanner should be able to pull off the "P" codes. They may even be able to tell you immediately if a specific component is heading for trouble. That engine is rock solid and rarely gives big problems. What I would suggest is that if you carefully take the top cover off, inspect all the small breather and vacuum pipes on top for chaffing, damage or disconnection. Any one of those gone astray could send the wrong fueling message to the ECU and create the symptoms you describe.
If you get a list of fault codes, don't panic! Most of them will be unrelated or cascade faults, so can usually be ignored. Let me know if you need any more info. I have access to a lot of information on the TDV8, but would need to see a fault code list first.

[Nomisb]

No fault codes at all on my fault code reader- which was more of a worry than having loads. Will check air filter

[diffwhine]

Think positive! Fault codes usually cost money...
Does sound like an air flow fault, but double check those small pipes round the top of the manifolds as well.
I'm inclined to suspect that its either an intercooler hose issue, or loose hose connections on the mass air flow sensor. Doesn't sound like a mechanical issue if everything is performing and driving OK

[Ndrwdz]

I'm also thinking intercooler hose.

We had similar symptoms when that failed on the FL2

Andrew

[Nomisb]

Think positive! Fault codes usually cost money...
Does sound like an air flow fault, but double check those small pipes round the top of the manifolds as well.
I'm inclined to suspect that its either an intercooler hose issue, or loose hose connections on the mass air flow sensor. Doesn't sound like a mechanical issue if everything is performing and driving OK

 

I got the thing for a song and it's probably worth more in bits so it's not the end of the world. I've just got rather attached to driving at 80 miles an hour in a Georgian living room....

[Nomisb]

May be a daft question but both exhausts go into a single silencer at the back - do the gasses remain split or do the mingle?

I only as as there is smoke coming out of both rear pipes - if the gases remain "sided" i.e don't mix it could be an intercooler problem?

[diffwhine]

They mingle... Anybody who's done a turbo on a TDV8 knows how much oil gets trapped in the exhaust. Very impressive smoke screen from a very capable oil reservoir (silencer).

[gilbo]

When you say you checked the hoses - did you check for delamination? And di you check them all? It can be hard to spot and I have no idea on this engine how many turbo hoses it hasand clearly it has shedloads of sensors and clever electronics. But ....... some years back on one of my 300Tdi Discos one of the hoses delaminated (quite common I think) and of course the effect is to reduce the airflow (as the turbo sucks the inner lining of the hose inwards!) until, in my case it stopped - in a massive cloud of black exhaust smoke. Annoyingly I had discovered the problem and was on my way to my local dealer to collect the new hose!!
I ended up walking ....and then fixing it at the road side!

[Nomisb]

Two hoses being held for me by local dealer - I've been told to look at all the hoses!

Thanks for all the help!

[Simon K.]

I think your motor has an ECU that learns/remembers as it goes along, you may have to clear recent readings from it so that it knows that you have nice new pipes fitted, and a proper airflow.
Simon.

[diffwhine]

Simon - you are correct, but it will also learn to adapt the correct way pretty fast, so there shouldn't be any need for concern there. The problem comes with gearboxes - especially automatics where they adapt as they wear. In the case of the JATCO box in the Automatic Freelander 1, dealers were changing the gearboxes, but there was no way to reset the adapations. As a result, a new box was pulled up tight by the ECU thinking it was a worn out old box. Guess what - premature failure of the new box... Only solution in those cases was a new ECU. We learned our lesson after the JATCO fiasco and it doesn't happen now thankfully.

[Gareth]

 Check the intercooler itself. Look for oily stains. A smoke test would help diagnose it. Could be a fault mass airflow sensor. Not sure about the TDV8, but on the V6 it’s just after the air filter, in the inlet tract.

[KLR875]

Another vote for inter cooler hose - can’t repair them and can’t see her hen split - swap them first before spending money on anything else

[diffwhine]

Simon - did you ever get to the bottom of this?