I have just returned from a 3000 klm round trip from Devon UK to The Algarve, Portugal, in my 2015 RR Vogue SE TDV8, a repeat of the same trip last March. On both occasions the trip was totally faultless, I can think of no better car to take on a trip of this nature, it certainly has very long legs and is very relaxing to drive over these long distances.
However, during my stay in the Algarve, I experienced a 'Restricted Performance message' followed by a distinct fall off in power, this happened approximately 5 minutes after a first time start up on that day, so the engine was not particularly hot.
I stopped the car and engine, and checked the handbook faults listings and found no reference to it.
I called the Range Rover dealer in Exeter to ask for comments on any past experience they may have on record, they could offer nothing other than a suggestion that I call International Assistance.
After being stopped for approx 15 minutes I fired up the engine and found it was running perfectly, and it continued to do so for my remaining two weeks in Portugal and in fact the return trip through Spain and France and back to the UK.
With one week still remaining in Portugal I decided it would be prudent to contact the Range Rover dealer in Faro. I was asked one question, ' Has the problem re-occurred', following my answer of No, I was told not to worry about it as it would probably not happen again !! he was right, it did not.
The car is shortly due for its first major service, so it will be interesting if anything shows up following this.
I would welcome any constructive comments on the above situation

Not heard of it on the L405 but any number of sensors could have caused it.

The advice seems good, just restart and see if it happens again An IID tool or similar or the dealer should be able to read the fault codes for clues.

The 3.6 TDV8 throws this message most often with a split turbo hose, but even then, you could just restart and take it easier and normal performance was resumed.

Thanks Alistair for your prompt reply.

Your comment: The advice sounds good, did make me smile. You are of course correct, but only in hindsight!!
I can assure you that when you are in The Algarve and about to make a 1200 klm trip up through Portugal, Spain and France, at very fast motorway speeds, it is/ was not pleasant having that unsolved problem on your mind.
Having the engine revs suddenly drop 80% without warning whilst in the fast lane was not something I was looking forward to, thankfully it didnt happen.
I have a background of many years rally driving, one of them being The epic London to Mexico World Cup Rally, the thought of that kind of engine speed drop off whilst driving at speed 3 miles up over the Andes in SA (on oxygen) does not bear thinking about. If you dropped off the edge of some of those drops, they would never bother to look for you !!!!!
I am also an ex deep sea marine engineerofficer, which is exactly why I would like to get to the bottom and understand the actual reason behind the 'Restricted Performance' message.
Fxxxxxxxg electronics !!!!!
RC

I got a restricted performance plus sudden drop in power when overtaking 2 lanes of hgv's which proved to be one of the 4 short hoses on the inlet manifold. ( easily detected by 3 being spotlessly clean and one covered in sooty black )
The MD changed all 4 under warranty as a " just in case " , but I am convinced there was nothing wrong with any of them, just one had come loose ( jubilee clip ) ?? G reg 2.5VM Vogue Portofino red 1991- 1999
V reg 2.5td P38 Rioja red 1999- 2006
53 reg td6 Vogue Oslo blue 2006- 2015
11 reg 4.4 TdV8 Vogue SE. Baltic blue 2015- date.
https://www.fullfatrr.com/forum/topic56162...tty+affair

Its happened on my Sport exactly as you described once when the car was a year old, it never happened again.

IMO enforced restricted performance should be outlawed. It's one matter for an engine to not be performing to it's usual level due to a component not working properly but to significantly reduce power because of a plausibility condition that suggests that something must not be quite right should not be allowed. I liken it to the earlier enforced lowering of the suspension when a fault is detected by ABS, prior to the revised rules of the current suspension modules where the driver is given the option to prevent the lowering. I have a tractor that by default will shut down the engine in 30 seconds on loss of oil pressure but provides an over-ride for use if stopping immediately would be dangerous, eg on a railway crossing.

I had a series of restricted performance events with a 3.0 Disco4 that basically made the car dangerous to drive. Restricted performance was triggered by plausibility logic in airflow and pressure measurements because the secondary turbo inlet isolation valve was sticking, causing the secondary turbo to not be used. For normal driving the lack of the secondary turbo would have made little difference to performance but purposefully limiting fuel to about 10% made a huge difference.

For the benefit of others, I thought I would pick this thread up again as the 'Restricted Performance' saga has only recently been resolved by the Range Rover Exeter Main Dealer, Nb: After 5 visits !!

The problem was eventually traced to the sensor in the back box of the exhaust system, this sensor is meant to trigger a burn off of soot residue that builds up in the box, if this fails the emissions go through the roof and way past the high side of the permitted maximum emissions levels which then triggers the 'Restricted warning light.

The sensor was changed 4 months ago and the dreaded 'Restricted warning light' has not been seen since, over a used distance of approx 2500 miles.

This original problem started 18 months earlier whilst in the Algarve, when I called Range Rover UK I was told there was nothing on record that showed up this error code when the diagnostics were plugged in, did they think I had invented it?

RFC7

ahhh DPF strikes again. At least they just changed the sensor. When my old L322 had this, the MD would have none of it and insisted I needed a complete new DPF.

Hi Martin,

I wouldn't have cared if they had changed the engine, it was still under warranty! Actually, that is not strictly true, however, it certainly was when the problem first reared its ugly head. Four visits later the car was back with the Range Rover main dealer again, this time it was still not sorted and the car was very close to its end of warranty. I insisted they agree to look at the problem should it re-appear outside of the 3 year warranty, it did and true to their word they took the car in again when the warning re-appeared, and on this occasion, they fixed it.

RFC7

Just got the 'restricted performance' warning myself last night .All I could remember before the warning was a few hours earlier when the car stuttered for a split second then was ok. Don't know what's causing it yet, it seems to limit the revs to around 3000 (checked this by putting the car in neutral and checking how high it would go). I also had the same knock on as per the other thread about this issue...
http://www.fullfatrr.com/forum/topic43912....erformance
on pushing the stop engine button, nothing happened for 3-5secs , I initially thought the engine was not going to turn off which would have been handy at 00:20am !! I left it for around 20secs then turned it back on again and still got the warning message and the delay stopping the engine again.
Not started it yet this morning but hoping it has self cleared overnight, otherwise I will be checking for loose hoses else the main dealer tomorrow  Steve

Main car : FFRR L405 Vogue SDV8
Other car : Vauxhall Lotus Carlton
Past cars : FFRR L322 Vogue TD6 SE (Sept 2006 MY07) ; LandCruiser SWB ; 4-Runner ; Supras; XJS V12 LeMans

Hi Steve,

My car:2015 Range Rover Vogue SE with 4.4 V8 diesel.

Firstly the good news, after first experiencing the dreaded restricted power problems at around 20,000 miles, which reappeared 4 or 5 times throughout the next 10,000 miles, it has now been sorted. (Fingers crossed)
It took 4 visits to the Exeter Main RR dealer before they solved the problem, which I was finally informed was caused by the failure of a sensor in the exhaust emissions back box. This sensor triggers the burn off of the exhaust deposits which build up in this collection retainer if the sensor fails, the soot deposits are not burnt off, they could then build to a level which could damage the engine. The onboard computer detects this and puts the engine into a restricted power mode.
I suspect this is a risk assessment factor because at this stage the high level of carbon deposits restrict the normal exhaust flow with the potential of passing this overload into the atmosphere and also restricts the correct breathing required for the engine to perform correctly.
What bothered me when I first reported the problem was the fact that I was told there was no such known message held within the computer coding !! The next time it happened I photographed the error message and showed it to the RR customer service manager.
It took 4 further visits before it was finally correctly diagnosed and a new sensor was fitted in April this year, to date there has been no recurrence of the problem.
Having read your post I am pretty certain your situation mirrors mine.

Good luck.

RFC7

Thanks RFC7 . I started the car Sunday morning and of course it was fine, however, I only did a few miles so may have temporarily cleared and a longer run may cause it to emerge again. I think I'll take it to the dealers and ask them to check/change the back box sensor as my symptoms mirror yours. I don't think it can be the turbo hose now etc as if it had split/come off, the issue would still be present I would hope , but I might have them checked in passing anyway when it's in.
Thanks again  Steve

Main car : FFRR L405 Vogue SDV8
Other car : Vauxhall Lotus Carlton
Past cars : FFRR L322 Vogue TD6 SE (Sept 2006 MY07) ; LandCruiser SWB ; 4-Runner ; Supras; XJS V12 LeMans

Hi guys, just been reading these points and I have had a similar issue. Engine performance. Mine comes on in the morning. Thank god for that. First time it happened this September 2019, while I was coming back from France to the UK. It was raining hard the last 200 kms from Calais. I didn't start nor use the car the next day, I think it stood for two days, and then in the morning when I started it, I got the restricted performance light. I warmed up the car, and drove out, in manual, shifting up in order to gain some spead. No unusual sounds, the car would just not rev more than 2000 rpm or less. After 10 mins or so, I switched of the engine, and it didn't switch off right away, there was like a 3-5 sec delay. I waited a bit, and then started the engine again, and the fault was gone! At that time, I found this post, and went to my dealer, and told them to change the sensor in the back box advised. They did that, and since then it was ok, no faults. Until last week. It has bee very very wet and raining in the UK, and I have enjoying going in to the pools of water all over surrey, I mean that is why we drive these cars. and again, the next morning, I got the same fault again. I drove for a bit, switched off, and the fault is gone.
And one more time, a few days ago, I washed my car with the jet wash, and guess what? Next morning, I got the fault again, I did my ritual, warmed it up, drove for about 10 mins, switched off, switched on, and it is gone again. The main dealer mechanics are idiots, they really have no clue what is wrong with these cars, because once the fault is not showing on the display, you can't take the reading, that fault is not being logged for some reason. So I don't want to bother going to them for investigation. We had another SD V8 in the houselhold, it was one of the very early models, and after 100k miles, it got this fault many times, the main delaer had it 5 times, and at the end they told me that it was leaking engine coolant, and they suggest to change gaskets and pipes and all sorts of things, the repairs cost over 3k, and then it still got the restricted performace. So if anyone here, who managed to sort a similar issue, I would really appreciate some feedback guys. I think it is something so simple, because it must be due to the fact of the conditions being moist/wet. Happy new year to all and thanks in advance.

Ive had the 'restricted performance' warning come on yesterday twice. same as others here. when i turned the car off it took 5 seconds after pushing the button for it to switch off. once left for an hour it was ok but soon afterwards it happened again. I took it into Wimbledon LR this morning and they ran a diagnostics scan. it seems to be some thing to do with the turbo. recommended procedures are to start with the wiring apparently, if those do cure it it ultimately means replacing parts. they cant book it in until the 19th August and when i asked if i could still drive it, they thought it would be ok to do so?

I wouldn't drive it if its likely to go into restricted performance mode sir... That type of advice is ludicrous! And only given as they don't have time to look into it...

Try explaining that to your insurance company when someone hits your car after a sudden loss of power!