JayGee wrote:

Thanks. Could do with a power decrease on mine - wonder if they can map out the 2nd turbo Laughing

Less power is easy...  Cam

2011 TDV8 Vogue in Stornoway Grey

JayGee wrote:

jaguar3 wrote:

How you duys solve/think about next things:

Diesel turbo engines don't need 'Blow-off' / 'dump' valves as the throttle plate doesn't shut when you come off throttle like a petrol engine so there is no intake pressure surge. Although it seems the TP does close if you blank the EGR valve as it tries to increase EGR flow.
Fuelling is controlled via MAP, MAF IAT and oxygen sensor so it will be fine.
Combustion temperatures will be higher with no EGR flow but as the EGR is only open at low load settings it's not likley to overheat. When you put your foot down the EGR closes anyway and EGT and in cylinder temps rise very fast but it's all within the cooling capacity. Imagine lugging a loaded trailer up a steep hill or pushing the brick like body through the air at 140mph on the autobahn - EGR shut by default in those high load situations .

Thanks for the input jaguar3. I see what you're saying and all completely valid points I think. What it comes down to, from my perspective at least, is the desire for the car to be running at its best and to provide an enjoyable driving experience. This is of course a very subjective thing for each of us, some like the idea of 'improving on LR's original design' in realistic approaches and can see both the benefits and drawbacks of doing so and of course some are happier to leave be and not disturb. I'm a pragmatic type quite accustomed to doing my own cost/benefit analysis in whatever area you care to mention.

Case in point being the EGR system; an inherently flawed system that's been in use for decades now that has added an additional layer to the inlet systems of vehicle engines and therefore point of failure, lowering efficiency, performance and reliability for a meagre reduction in harmful emissions. LR in the case of our 4.4 diesels has sought to design in additional benefits of the system in the form of excess pressure protection under full boost overrun conditions and a reduction of engine-drag off-throttle.

Now I personally don't mind the increase in engine drag off throttle as I find suits my driving style, both if 'motoring-on' and when 'hypermiling' it allows me to keep away from the brake pedal as much as possible. Also by mapping and blanking the EGR, the increase in economy is quite pronounced

The pressure relief is another matter; it doesn't personally affect me and I would argue it wouldn't affect the majority of RR drivers - there is the potential for boost to spike, but the conditions for this to happen require a very aggressive and mechanically-unsympathetic driving style. If this is the way you prefer to drive then yes, I would recommend having a blow-off valve fitted and you'd likely want the big whooshy noises and all to go with. I'd also argue if this was your way of driving you'd be less inclined to worry about your emissions anyway and would probably swap your DPF for a straight-through exhaust. That said, why would you then own a diesel and not a petrol supercharged V8? Cam

2011 TDV8 Vogue in Stornoway Grey

Thanks for justified opinion protection.
No, Iam not agressive driving-style driver at all. I has a many petrol V8, like couple of Grand Cherokees, Jaguar, Hummer, so this stage is over for me long time ago, enough. For sure no any whoosy noises or some kind of stupid things like that. You take me wrong. But of course still, sometime I need to use kick-down, especially if 4,4 can provide me a great acceleration.
But most of time yes exactly the same, as less as possible touch the brake pedal.
Also Iam not "green-crazy", so this is also not the reason.
I just worry about consequences, EGR valve is not just added later when engine was done, its there from the beginning and its integrated in the system. Engineers build the engine considering EGR existens, all is depending of everything.
Is almost the same like, lets take 2 pistons off and make V6. Why not? Its possible, the engine will run. But all of other systems are designed for working as V8: cooling system, flywheel mass, turbo pressures etc...etc...etc.
Same with EGR. its very difficul to keep in mind and adjust all systems to work without EGR. It must be very smart and professional engineer who will remapp whole the system to work according new conditions.
If you only just "swich it off" and just close the holes, this is not right approach I suppouse. You will find a problems. Not today, not tomorrow. But in future.
And one more thing. If you have later some other fault (even not depending of EGR at all), its much more difficult to find the problem if system is changed and remapped. Because LR mecanics just cant find the problem, he have no clue what is original and what is changed before and wich way its changed. Many mecanics just hands up immidietly when they heard about some modifications are done with the car, especially engine. They need new repearing manual, this is not the same car anymore. Thats true.

Not being facetious or implying you in any of my stereotyping jaguar3, just giving you my honest opinion while keeping a little humour for all reading the thread.

I think I would dispute your analogy of the EGR being as important to the engine as a pair of pistons, but I respect your point. That said, I think you perhaps accredit LR (or FORD in the case of this engine) with a little too much praise for their design process. Most engines are simply revised designs of earlier versions with new models having incremental changes/improvements based on a number of small technological advances and lessons learnt from outgoing models i.e. identified weaknesses in cooling/induction/combustion/exhaustion/fluid routes etc

The EGR system was introduced many years ago in an attempt to reduce specific emissions from exhaust systems to appease green lobbies/politicians and is a bolt-on to the engine that it doesn't need to function. Yes it is integrated to a much greater degree these days as is everything associated with the running of the engine and simply pulling it out would create issues for a system expecting to see it. I would analogise it to being more equivalent to the Air Con system as far as the engine is concerned.

Also there are many owners here that are happy to take their cars to LR and allow their mechanics to deal with all aspects of maintaining their car. I would think none of these owners would consider doing anything to their cars that deviated from the 'norm', certainly not install a remap with EGR delete. I happen to one of the other type of owners who does all his own maintenance and is aware of all that has been done to the car and the potential consequences of such.

Anyway, I hope you don't consider anything I have said as a slight on your opinions and comments. That is not the intent and I will always welcome healthy debate and discussion  Cam

2011 TDV8 Vogue in Stornoway Grey

Not agree about Air Cont comparsion. Its too simple separate system, not affecting anything. But EGR, here we talking about fuel burning process, heart of engine.
Other things yes, absolutely confirm, EGR is made for reducing emissions and nothing else. Engine manufacturer have no choice. Actually they have: or you install the EGR, reduce emissions and can start producing engines, or you will not produce anything at all.
Due they have no choice, they try to live with that and integrate it in engine, consider temperatures, air flow, burning activity, needed amount of oxygen etc. But now you take it off and change engine working conditions. I mean you need to change a lot of parameters to get it working well in new conditions. That mean new and and hopefully good remaping.
My only question is why? The system is not so bad as it was 20 years ago and its works quite well and didnt make you any problems as old EGR-s doing years ago.
It dosnt affect you as car user anyhow, final result is the same, you still sitting in your comfortable seat and enjoy the voyage, with EGR or without it.
Thats only thing I cant anderstand (of course I can anderstand if EGR is always faulty, check engine light come on, power reducing, fuel consumption rise significaly, you need to clean intake every 30000 miles or even less, repearing is expensive etc). But what is wrong with that one?
Just enthusiasm?
Dont take me wrong, its not slander your opinion, its just a discussion. Without different opinions there is no progress and probably we still ride a horses.

jaguar3 wrote:

Not agree about Air Cont comparsion. Its too simple separate system, not affecting anything. But EGR, here we talking about fuel burning process, heart of engine.

Then we will have to agree to disagree, because for me it is not part of the heart of the engine or needed for the fuel burning process; it's there for us organics to breathe slightly less toxic air at the cost of engine performance/efficiency hence the Air Con analogy.

So your point being and I'm paraphrasing here 'if it's not broke, don't fix it'? Well I contest that the inclusion of the EGR is breaking the potential of the engine and creates conditions that make a failure in one of the intake components inevitable. We recirculate oil vapour through the intake and then we add hot sooty gases to the mix creating a sticky, abrasive goo that destroys moving parts and clogs sensitive sensors. Remember all the swirl-flap failures that got ingested through various manufacturers' diesel engines? MAP sensors giving erroneous readings? Air flow disruptions interfering with inlet charge? Caused by that gunk. Not to mention the EGR valves themselves clogging up and sticking open or shut.

In my case, as described fully earlier in this thread, I developed an EGR fault that was going to be a 'painful' fix so in my eyes it was a no-brainer to delete EGR in my upcoming remap. As a result, I have experienced only positive results in my driving since the modification. If your argument against this is that my LR may develop a fault later on down the line, you may as well predict that day will follow night...  Cam

2011 TDV8 Vogue in Stornoway Grey

Ok, lets finish our discussion like that: until I dont have any issue with it I will not remove it for sure.
If I have just some sensors dirty, I will clean up and not touch EGR. If I have fully dirty intake and I need to clean it up, I will clean it, but still not remove EGR, because its too late, first owner must do it.
But if I have some fault of EGR unit it self and repearing cost is high, I will also think about removing.

What’s the actual mpg gain you are seeing? 2012 TDV8 Vogue (L322)

I don't know whether this is relevant to this topic, but when my engine is stone cold the throttle pick up is instant and clean and gradually gets more laboured as the engine warms up. Presumably the EGR isn't working until up to temperature?
Also I have lots of engine braking for the first mile or so.
You guys seem very knowledgeable so excuse me if this has nothing to do with the EGR.

EGR isn't enabled until the engine gets up to a defined minimum temperature. I centainly notice that mine drives much better until it starts to warms-up but that could be partly because more fuel is probably being injected for the cold engine.

kevinp wrote:

I don't know whether this is relevant to this topic, but when my engine is stone cold the throttle pick up is instant and clean and gradually gets more laboured as the engine warms up. Presumably the EGR isn't working until up to temperature?
Also I have lots of engine braking for the first mile or so.
You guys seem very knowledgeable so excuse me if this has nothing to do with the EGR.

JayGee wrote:

What’s the actual mpg gain you are seeing?

I'm 30+ mpg average on tank fill vs trip and see similar instant mpg. The CCF instrument panel settings are 7% optimistic for mpg readout so fill to brim vs trip miles are the only accurate way to measure it unless you reset it like I did with the GAP IID tool. What was it before the EGR delete? 2012 TDV8 Vogue (L322)

When I calculated it, the onboard was almost exactly correct. Yes I measure it properly; brimmed and trip reset each time. I was low to mid 20s before remap and EGR delete. Driving style; I like to get up to speed quickly and then try to keep it constant and avoid brakes as much as possible. Cam

2011 TDV8 Vogue in Stornoway Grey

If it was low to mid 20's that's quite a gain  2012 TDV8 Vogue (L322)