Have you looked at the MAP sensor yet to see if it needs cleaning Ash?
Hope the 'bung' solves it's oil appetite.

I haven't and will do today, but all through this journey so far, the sensor was always clean.

Will post back this morning though. Ash
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2022 SDV8 AB
2016 TDV8 VSE
2011 TDV8 VSE
2006 V8 Vogue
2002 2.5 Vogue

So - second day of the oil filter replacement - no loss of oil and no smell of anything burning - still looking good.

I checked both the MAF Sensors - and again, both perfectly dry and clean, but gave them a squirt anyway.

Also decided to check the sensor on the top of the doughnut. No idea what it is/does but it was black with oil. Also gave it a squirt and a gentle wipe off and reinstalled.

Went for a drive to warm the car up and thought…. Let me just try.

Open road and a bit of a hoof took her up to 3k and backed off…. All good…. Same again up to 4k…. Pulled like a freight train and backed off again. Turned round and again put my foot down and straight up to 3-4k around 3.5-4k revs…. All good.

Back to normal driving and all of a sudden, car sounded like a rattle can old taxi and within 20 yds Restricted came up.

So the issue isn’t resolved (which I didn’t think it would be just by fixing the oil drain back) but strange the way it let me hoof up past 4k revs with no issues. Ash
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2022 SDV8 AB
2016 TDV8 VSE
2011 TDV8 VSE
2006 V8 Vogue
2002 2.5 Vogue

Does the fault now occur only with gentle driving, being good if worked hard? If so then sounds like something is sticking on light throttle, perhaps that turbine valve.

The sensor on top of the donut is the MAP sensor which clogs due to EGR + oil vapours.

Hi Greame

No I don’t think so. ‘Driving miss daisy’ is 100% fine.

I thought I’d give it some beans earlier and a few goes seemed absolutely fine. It was after the 4th sprited drive that I backed off… and not long after it went into restricted.

Just went out again and, joining a dual carriageway, I gave it some beans up past 3,000 and it was fine, accelerating well, and I just backed off and continued my journey with no issues. Ash
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2022 SDV8 AB
2016 TDV8 VSE
2011 TDV8 VSE
2006 V8 Vogue
2002 2.5 Vogue

Hmm…

Further update. Went on a longer drive today and, with the car warm, a little ‘spirited driving’ along some lanes, no issues. Pulled hard through the gears and up through 3-4k revs and all was fine.

Got onto a dual carriage way and, doing ‘about’ 60 (ish), went to overtake car infront, car dropped down a gear or 2 and powered away….. up through 3k revs….. but then felt a little knock (like the gearbox jumping a little harsh into gear) and heard a small sound, not very loud at all and into restricted performance again.

Pulled over and turned the car off… waited a minute and then started again, all clear and off I went.

Didn’t try the same on the way home but again on the back roads near home, up through to over 3k revs and all good.

Seems a little temperamental at the moment so will take it easy and monitor things. Still no loss of oil or anything. Ash
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2022 SDV8 AB
2016 TDV8 VSE
2011 TDV8 VSE
2006 V8 Vogue
2002 2.5 Vogue

sorry folks - me again.

Car has been behaving very well this last week - I’m really enjoying the driving experience round town with the power back again to pull away rather swiftly - These 4.4s really do have some pulling power…

However, I’m wondering now if there ever really was an issue at all with the 2nd turbo or the connection to the restricted performance.

Had to take a drive out to Addenbrooks this morning, a nice 1 hour trip on Motorway and dual carriageways. Now it seems I can still enjoy spirited driving but, with medium but constant throttle, the revs build to just a shade over 2k (not close to 2,400 for the 2nd turbo to kick in), the car changes up through the gears just fine, but then i get restricted performance again. By no means aggressive driving.

Given this does not seem to be related to kicking in the 2nd turbo would I be right in saying its not the secondary turbo shut off valve..? (Not the CSOV, but the one attached to the back of the turbo)

Surely that would only be an issue when its called upon?

I’ll clean the sensors again when I get home as I guess the whole air intake and 2nd turbo has had 9+ litres of oil put through it over the last 6 months due to the missing ‘bung’

Any ideas where I be looking next?

Thanks as always Ash
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2022 SDV8 AB
2016 TDV8 VSE
2011 TDV8 VSE
2006 V8 Vogue
2002 2.5 Vogue

Ash, I presume you have looked at the plenum chamber hoses to make sure they arn't split anywhere?
Is the hose to the throttle body tight? Should be perfectly dry. Any misty oil there shows it's leaking.
Glad to hear it's not using oil now.

My gut feeling: The CSOV is changing over to the 2nd turbo ... but not changing back as well as it should. This would explain why you can drive it hard, but it fails when going back to normal driving. V8 or else ...

DTCs?
Sounds like an intake pressure/flow plausibilty issue MAF vs MAP values.

Thanks Fisha,

To be more accurate, I can drive it hard and it behaves perfectly and when I slow down it’s also fine. I can continue to drive normally, and continue with more robust driving or gentle driving and it’s still fine

Then I might need to join a dual carriageway and drive as des ones with ‘sensible’ acceleration, steady throttle up to around 2k, nothing harsh, and it will drop into restricted. I don’t notice much loss of powers but will gently start to slow down.

GraemeS - the codes are still the same as my first post in this thread [url] https://www.fullfatrr.com/forum/topic70038...c891[/url] and do seem to relate to a plausibility issue.

I’ve swapped the sensors across and the same happens so the sensor itself seems to be fine.

Kevin - I’ll look tomorrow but LR said they had performed a pressure and smoke test and saw no signs of leaks. I just need to find the right pdf in the WSM to identify all the parts to check Ash
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2022 SDV8 AB
2016 TDV8 VSE
2011 TDV8 VSE
2006 V8 Vogue
2002 2.5 Vogue

OK - makes sense what you're saying, so CSOV likely working just fine. Based on that, and the original plausibility errors, my next initial thoughts / comments:

That something like your fuel trims / adaptations are going out of whack to the point of generating an error. My understanding and experience is that fuel trims / adaptations adjust during medium acceleration. At low speed and firm acceleration, they don't. So this ties in with your above comments of driving style where its the medium acceleration which leads to the error.

So to me, trim levels adjust based on monitoring what the sensors are reporting back. It knows what it should be in theory, but if the sensors start to drift their readings out of spec, then the ecu will add more / less fuel to match ... but will realise this is causing an error through watching the emissions change ... so it then applies a trim adaption to the sensor reading before calculating fuel amount, so that the emissions remain ok.

But there is a limit to how much it can adapt. You normally have short term trim, and long term trim. Short term jumps about quickly to maintain short term changes, long term adjusts over a more averaged time period. So if the short term consistently is high, then after a period, the long term will adjust higher to match, allowing the short term one to reduce back to a neutral amount for it to jump about.

It the short term one stays high, and the long term one keeps going higher and higher, but isn't making a difference, it'll reach a limit, and error out.

Going back to your original error ... plausibility error ... so the ecu cant reconcile the equation of air, fuel and emission. So something is telling it a duff value. .... hard part is finding which.

all the error codes, and descriptions are within the Service Manual > General information.pdf file. V8 or else ...

Hi Gang,

I think I'm getting somewhere now, although strange it still seems a little intermittent..

Have only fallen in to Restricted Performace a few times lately, seems to pull like a freight train for most round town driving but play silly when already doing 30+ mph and decide to accelerate... No idea why.

Today, with IID plugged in, i tempted her into Restricted again and, without turning the engine off (which seems to clear the fault), I managed to pull the following...




This now seems to suggest a mechanical failure of the Actuator being stuck.

I pressume this is now not the secondary turbo shut off valve itself .. I think it is the thing that does the shutting/opening of that valve.?

Is it a case of 'lubing up' to free it off and see how it goes, or is it better to just replace it?

Finally - Do you think this is a Driveway DIY'er job or better to book in somewhere?

Many thanks all as always. Ash
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2022 SDV8 AB
2016 TDV8 VSE
2011 TDV8 VSE
2006 V8 Vogue
2002 2.5 Vogue

Dtech wrote:

When I first purchased my L322 4.4 tdv8, I had the same restricted performance issue when exceeding 2400 rpm. Having replaced all relevant inlet hoses, and checked that the CSOV valve operated ok, I came to the conclusion that it must be a problem with turbine shut off valve on the left hand turbo ,because no matter how hard I pushed the engine, the left exhaust front pipe was still cold.
The shut of valve, unlike on some turbos is a vacuum operated sliding spool with ports in it. If the turbo is never used, usually by a very elderly driver, as was the case with my vehicle prior to my ownership, i think carbon builds up around the valve and prevents it sliding.
I cured mine, by connecting a hand operated vacuum pump to the vacuum pipe which I disconnected from the valve at the front of the engine. I kept pumping the vacuum as high as it would go, and then quickly released it, I also tapped on the valve with a small hammer. Eventually after a number of attempts at pumping the vacuum and releasing it I could hear a slight clunk as the valve closed.
Needless to say I have never had the restricted performance issue since. As others on the forum have pointed out, it is a good idea to routinely work the engine hard enough to operate the valve to prevent it sticking. There was also quite a bit of oil contamination on the junction of the down pipe to the turbo which has now burned off.

The left hand down pipe can only become hot if the turbine shut off valve opens, but this would normally only happen when the engine rpm and load reaches the required level to activate it.
Although I seem to recall reading somewhere that it’s programmed to periodically open to keep itself free. This maybe what you heard. By what you describe it sounds as though yous isn’t seized.