Sport Fuel Pressure Issue RRS 2016 TD6

I know you're tired of seeing RR fuel pressure issue threads but I've gone through so many of them and I can't find one that fits my situation:

Quick Summary:

Car: 2016 RRS TD6
Situation: Car turns on smoothly and drives/runs normally until I go above 50km/h or so then it goes into "restricted performance". If I kick it down the car stalls but I can turn it back on and drive again after few seconds.

DTCC codes I've gotten:
P0088-72 PCM 92,917km Fuel rail/system pressure - too high
P0087-84 PCM 92,915km Fuel rail/system pressure - too low
P0087-21 PCM 92,915km Fuel rail/system pressure - too low
P0087-22 PCM 92,915km Fuel rail/system pressure- too low

First culprit was the fuel railway pressure sensor, changed that to official part, that's what live data is showing:

When I first turn the car on, pressure starts at 6000psi then drops to around 4800psi:


When I gas the car the pressure increases as the RPM goes up:


Are those normal railway fuel pressures? (should the standard range really be 0 to 3000 like the scanner says?)
What other tests can I do or values I can look at to pinpoint the problem?

Do you think the fuel return could be restricted somewhere?
Can the Fuel Rail Pressure Control valve (PCV) cause this?

Any insight will be highly appreciated!

Thank you in advance,

I would say 3000psi is to low for a running engine, iirc most common rail needs 200bar just to start, which is roughly 3000psi.

Any videos on youtube, does not have to be your specific engine, any common rail unit will give you an idea or two.

À simple leak off test of all the injectors while they are in the engine. Any difference in returning diesel will tell you straight away.
It could be a sticking injector.
The amount of small parts in the injectors can stick during their operation giving high /low fuel pressures. That's the quickest way to rule out the injectors without any heavy intervention.
Then if you do have differences, the ideal thing is to replace all six injectors as another will follow due to age/mileage

lynall said:

I would say 3000psi is to low for a running engine, iirc most common rail needs 200bar just to start, which is roughly 3000psi.

Any videos on youtube, does not have to be your specific engine, any common rail unit will give you an idea or two.

Click to expand...

Since you confirmed that the Desired Pressure of 0 to 3000 indicated by the ECM is wrong (and maybe the ECM is putting the engine in restricted performance because it's way out of that wrong range), it brings me to an important suspicion I left out:

The entire problem started literally a few hours after I did the mistake of letting a "potential buyer" plug in his tool/scanner to my car because "he wanted to make sure there's no major issues before he buys".
Given that, is it possible that the tool corrupted a file or he did something on purpose to lowball me on the sale price later?
Possible scenario or complete coincidence and bad luck?

georgesantos said:

Since you confirmed that the Desired Pressure of 0 to 3000 indicated by the ECM is wrong (and maybe the ECM is putting the engine in restricted performance because it's way out of that wrong range), it brings me to an important suspicion I left out:

The entire problem started literally a few hours after I did the mistake of letting a "potential buyer" plug in his tool/scanner to my car because "he wanted to make sure there's no major issues before he buys".
Given that, is it possible that the tool corrupted a file or he did something on purpose to lowball me on the sale price later?
Possible scenario or complete coincidence and bad luck?

Click to expand...

What tool did he use?
Did you watch him whilst it was plugged in?
How long was he plugged in for?

Did you watch him the entire time he was looking at the car?
Was he under the bonnet, maybe swapped/unplugged something?

If just a simple code reader, then no he should not have damaged anything, or even been able to.

georgesantos said:

Since you confirmed that the Desired Pressure of 0 to 3000 indicated by the ECM is wrong (and maybe the ECM is putting the engine in restricted performance because it's way out of that wrong range), it brings me to an important suspicion I left out:

The entire problem started literally a few hours after I did the mistake of letting a "potential buyer" plug in his tool/scanner to my car because "he wanted to make sure there's no major issues before he buys".
Given that, is it possible that the tool corrupted a file or he did something on purpose to lowball me on the sale price later?
Possible scenario or complete coincidence and bad luck?

Click to expand...

Not at all, diagnostic tools are not designed to interfere or change parameters.. It may just be a coincidence

lynall said:

What tool did he use?
Did you watch him whilst it was plugged in?
How long was he plugged in for?

Did you watch him the entire time he was looking at the car?
Was he under the bonnet, maybe swapped/unplugged something?

If just a simple code reader, then no he should not have damaged anything, or even been able to.

Click to expand...

I was with him all the time, definitely didn't do anything under the bonnet. He used a THINKCAR OBD2 Scanner (can find that on amazon) and was plugged in for around 10-15mins, but I did not see what he did on the screen that's why I am suspicious.

I wonder why it's showing that 0 to 3000psi "standard range" on the railway pressure live data, I plugged the same scanner on another 2018 range rover sport to see what "standard range" it would show me but it did not have any range at all, just shows the value and unit. So that got me thinking there might be something corrupt with the ECM.

Will do some further tests and circle back! Thank you!

10 to 15 minutes is a bloody long time to be plugged in, even if he was searching various ecus for their stored mileage.
Should literally take 5 minutes at the most.

Tool looks pretty basic on youtube, so hopefully it was not him.

lynall said:

10 to 15 minutes is a bloody long time to be plugged in, even if he was searching various ecus for their stored mileage.
Should literally take 5 minutes at the most.

Tool looks pretty basic on youtube, so hopefully it was not him.

Click to expand...

Not if your being thorough, live data is the tell tale for problems. When you know how to read them