So today I was on my way to Silverstone. When suddenly while driving along the M40 I get the "Restricted Performance" warning and the red triangle.

I noticed a definite bit of air whistle while the warning was on.

After being parked up for a few hours, the warning had gone and it was driving normal with no problems, then after a while at a constant speed, it came back on again.

I'm certainly no mechanic, but I'm thinking the fact it can drive fine after being parked up would probably mean that something is sticking/jamming somewhere, otherwise it would be running on less power all the time. And the warning would be staying on.

So, any ideas what the cause may be? I've seen a few different threads on ere but it seems there are various things that can cause it. But hopefully some can already be ruled out due to it being able to run o.k. after sitting for a while.

Start with having a look for any codes that might appear. I had this happen during the summer and took 5 trips to the dealer to remedy a cross over pipe issue.
With this said, restricted performance can be due to a lot of issues. Mine did exactly the same and rarely showed a code that was the gremlin, I did towards the end have the smell of exhaust in the cabin, they found the cracks in the cross over pipe.
It's a painful journey diagnose this error. 2018 Telsa MS
2012 Range Rover Sport HSE+
1990 Porsche 944
1985 LR 90 Soft top V8

Yeah. I did a search first and there seemed to be numerous different things being done by people to try to remedy the error.
Seems it is a very general message for a lot of different things.

I've just ordered a new ODB code reader which should be here tomorrow (the one I have is VAG specific, so I didn't want to try plugging that one in). So hopefully might get some kind of error code to possibly point towards the right direction.

Puslinch wrote:

Start with having a look for any codes that might appear. I had this happen during the summer and took 5 trips to the dealer to remedy a cross over pipe issue.
With this said, restricted performance can be due to a lot of issues. Mine did exactly the same and rarely showed a code that was the gremlin, I did towards the end have the smell of exhaust in the cabin, they found the cracks in the cross over pipe.
It's a painful journey diagnose this error.

Thankfully it was under warranty and replaced a melted fuel line at the same time, body on. 2018 Telsa MS
2012 Range Rover Sport HSE+
1990 Porsche 944
1985 LR 90 Soft top V8

New reader arrived today.
Hooked it up and got:

P006A MAP Mass Or Volume Air Flow Correlation.

A quick google for P006A on a Range Rover Sport seems to point at 3 possibilities.
Faulty MAF sensor
Cracked inlet manifold
Sticking turbo solenoid valve.

Although no actual idea if it is one of those things yet.

Thinking about it, I'm guessing it's not going to be the MAF sensors, a if one of those was faulty, the warning would be on all the time.
I'd have also thought if it was a cracked inlet manifold, then that would also be affecting it all the time. So I'd suspect a sticking solenoid.
Obviously, I'm just going on looking at it logically. But we all know there is very little logic to these engines at times!

The intake pipes are the most likely in my opinion, this was a very common fault over on the FFRR forum. My 4.4 TDV8 had two of the four inlet pipes split when i was getting the restricted performance. The manifold doesn't show all the time as when the engine is just steadily moving around town it's not under much pressure. As soon as you get on the main roads and load it up it starts sucking and opening up the splits.

Goos luck, let us know how you get on..  Current: 2010 RRS 3.6 TDV8 HSE
Past: 2012 4.4 TDV8 Vogue
2007 3.6 TDV8 Vogue
2005 3.0 TD6 Vogue
2007 D3 Commercial
2001 D2 4.0 V8 ES
1998 D1 3.9 V8 ES
1988 3.5 V8 EFI Vogue
Others: 2007 VW Touareg 3.0 V6
1998 Jeep Grand Cherokee 4.0
1990 Mitsubishi Shogun 2.6

After driving it today, this actually sounds very likely.
When accelerating I get a definite sound of air, which I’m pretty sure wasn’t there before.

Slightly late follow up to this.
But it turned out to be the offside inlet manifold.
Had a pretty big split. Found with a compressed air test, as it couldn’t be seen visually.
So all has been good for a while now (probably just jinxed it now lol) 2010 RRS 3.0 TDV6 HSE
1992 Mazda RX7 FD3S

Its good to see you posting up the final fix. So many times people ask for help and get various replies but never come back to say how the problem was solved.

Ditto above!! Glad to hear you are all sorted..  Current: 2010 RRS 3.6 TDV8 HSE
Past: 2012 4.4 TDV8 Vogue
2007 3.6 TDV8 Vogue
2005 3.0 TD6 Vogue
2007 D3 Commercial
2001 D2 4.0 V8 ES
1998 D1 3.9 V8 ES
1988 3.5 V8 EFI Vogue
Others: 2007 VW Touareg 3.0 V6
1998 Jeep Grand Cherokee 4.0
1990 Mitsubishi Shogun 2.6

Had exactly the same - but with my LR Discovery. Pretty expansive reparation.