2012 4.4 tdv8 - Had a red DFP Visit Dealer DPF blockage - Vehicle world not regen using Forced Regen with IID tool.

Have had the DPF chemically cleaned and reset. Car now runs but with the following issues:

Differential Pressure Senor reading in IID shows N/A, possible inhibiting the regeneration process. Have ordered a replacement sensor.

Car starts and runs perfectly at stationary idle and revving up to 4000 revs with engine coolant temperature at 105 Celsius.

When driving on level at up to 70 MPH engine coolant temperature rises to 115 Celsius.

When driving up even a slight incline on the motorway, the engine coolant temperature increases progressively with the coolant temperature indicator moving all the way to the right of the temperature scale, with an Engine Overheating warning appearing at 120 Celsius coolant temperature..

When I slow down and let the engine idle it quickly returns to 105 Celsius.

Have ordered a new thermostat from Duckworths, but thermostats are on back order with no indication from Land Rover as to delivery time scales.

Has any member encountered the same issues and possible resolution?

I have had three years trouble free use of the car and would like to get it running properly again.

Any advice greatly appreciated.

Update:

Reset Vehicle Adaptions using IID tool this morning. DPF Differential Pressure Sensor readings are now showing, but constant 25v and 20 Kpa. So looks like a duff sensor.... Will replace when arrives and update. Will take the car for a run this morning to see if there is any change to the overheating issue. 2012 4.4 TDV8 Vogue SE Current
2015 E220 with AMG Sport Pack - Currently driven by my son
2010 3.6 TDV8 Vogue - Written off by my son

WRT the differential pressure sensor, take it off the pipes and check for moisture / chemical contamination. Also blow down the pipes, doesn't need to be high pressure, just to check for a blockage or restriction. With the sensor pipes disconnected - or even with them connected and the engine stationary, you should get 0kPa, or very close to it.
Don't be tempted to 'blow through' the sensor, it won't work and you'll potentially damage it.

Resetting adaptions without first checking the actual values are plausible can cause further issues as you'll essentially put an offset on the sensor value.

Many thanks for your reply Phoenix.

The pressure sensor was showing pressure readings of 30 to 40 Kpa during some tests yesterday, but never dropping back below 20 to 30 Kpa. I have ordered a new Differential Pressure sensor, which should arrive early next week. Will report back once fitted.

I am not confident that the differential pressure sensor alone results in the over heating issues... I am wondering if the chemical clean of the DPF was successful.Soot levels were down to 2.2 g. after the clean and are now around 8.0 grams and not increasing rapidly.

The car runs normal on the level the issues arise when the turbos are engaged on hills and even slight inclines. I checked for bubbles in the top of the coolant tank yesterday, none show when the engine is running. I was able to burp a few small bubbles out of the system yesterday, I wonder if there is a airlock in the system.

I am considering removing the thermostat altogether as none are available in Europe at all at this time. Thermostat is on back order through Robin at Duckworths.

Any advice on why there is considerable pressure in the cooling system and what steps I can take to resolve that issue will be greatly appreciated.

John 2012 4.4 TDV8 Vogue SE Current
2015 E220 with AMG Sport Pack - Currently driven by my son
2010 3.6 TDV8 Vogue - Written off by my son

Hi John, I fitted a new expansion tank and although I didn't have an overheating issue I struggled to get a consistent level in the tank.
I remember loosening the bleed valve on the actual tank which resulted in a lot of bubbling and burping which initially made the level rise in the tank but after it cooled I could add quite a bit more coolant and the level has remained stable ever since.
Worth a try?
Kev.

Hi Kev,

Many thanks for the advice.

Schedule this morning is to remove the thermostat completely, then refill and bleed the coolant system as per the workshop manual. Will also follow your additional advice.

Noteworthy is that whilst the cooling system is pressurised there is no coolant loss, bubbling in the reservoir (indicating a head gasket leak), or oil in the coolant.

One question I have is:

The innards of the 4.4 V8 petrol thermostat, which is readily available, appear to be the same as those of the 4.4 TDV8. Would fitting these thermostat innards be detrimental to the system?

John 2012 4.4 TDV8 Vogue SE Current
2015 E220 with AMG Sport Pack - Currently driven by my son
2010 3.6 TDV8 Vogue - Written off by my son

The 4.4 petrol engine is a BMW unit, the 4.4 diesel is a Ford engine... can't see the thermostats being the same...!!

If you do remove the stat, check if it is faulty with some boiling water, plenty of YouTube vids on it....

If it isn't faulty, and it runs cooler then you could be fixing the symptoms but not the cause, so beware...  Pete

__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-

Hi Pete,

Many thanks for the advice....

As an update on this morning's activities... I have been bleeding the coolant system in accordance with the workshop manual. It now sits at 85 Celsius on idle and stays between 85 and 97 or so when driving normally.

Today, only when driving up an incline did the temperature rise to 115 Celsius and the needle on the gauge starts moving to the right,but stays in the black.

Whilst driving up the same incline on the A/M20 yesterday the temperature rose as far as to trigger the red over heating warning message.

So the overheating only occurs when the turbo increases output.

There is no coolant loss, there are no bubbles or oil in the coolant tank, and I can only occasionally get very small and single bubbles to show in the coolant tank.

John 2012 4.4 TDV8 Vogue SE Current
2015 E220 with AMG Sport Pack - Currently driven by my son
2010 3.6 TDV8 Vogue - Written off by my son

Cheapest things first and IMHO that could be an air lock... maybe try bleeding it a few more times... Pete

__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-

Hi Pete,

Yes that is exactly what I have been doing all day and there has been a vast improvement. Still not there yet but temperature is more stable now.... I was able to drive several inclines this afternoon without the needle moving from the vertical, albeit with the heater on full blast....

Its a long winded process bleeding the system - Put heater on full blast, rev to 3000 revs until heater blows hot, then set heater to minimum temperature and speed then switch the engine off. Let engine cool down and then bleed the air out. Repeat until there is no more air in system.

Whilst waiting for the engine to cool down I took the opportunity to sort out the loose throttle body inlet hose, which I believe was causing DPF issues.

I bought a pack of five Nitrile 75mm ID x 3mm C/S O Rings.

These are the o rings in question: https://www.ebay.co.uk/itm/293312881920?var=592174991355

Note; they do not replace the green o ring, which remains in place, the above o rings slide over the throttle body neck up to the point where the neck diameter increases.

I slipped two of these over the throttle body connection and refitted the plastic coupling. One single o ring was insufficient as the connection was still loose, three o rings and I couldn't get the clip back in. Two rings gave a perfect tight seal after using a small flat bladed screwdriver to push the clip tightly into the slots. The connection is now rock solid with no movement at all.

Also checked the MAP sensor, which had been cleaned on the last oil change 200 miles ago, it was clean.

Will continue the bleeding process again tomorrow and report back.

I closing I called Barret's, the local Land Rover dealership in Ashford, Kent yesterday and was quoted £500 labour. I believe the thermostat can be replaced in one hour, two at the most. How can these people justify such charges.

Overall it's been a productive day.....

Thank you everyone for your advice....

John 2012 4.4 TDV8 Vogue SE Current
2015 E220 with AMG Sport Pack - Currently driven by my son
2010 3.6 TDV8 Vogue - Written off by my son

DPF differential pressure is not available directly on the GAP IID tool so you have to look at the voltage and then reference the workshop manual to see the operating range under different loads and RPM's

"I believe the thermostat can be replaced in one hour, two at the most. How can these people justify such charges."
Just had mine done but the workshop procedure is to remove the whole coolant 'mixing box' and getting to that takes time and can lead to damage to more parts as the plastic is weak and brittle with age. Also the availability of the parts is an issue so make sure they can source the parts before you book it in. The thermostat and it's housing can be removed without taking the whole lot apart but this part is not available separately

Click image to enlarge

Thanks for the advice JayGee,

In that case the £500 quoted by Land Rover is reasonable, also bearing in mind the hassle bleeding the coolant system, the price quoted is acceptable. From your advice the there is the possibility of additional parts being deemed necessary by Land Rover taking the price quoted well above the cost of the thermostat and £500 fitting quoted.

The thermostat is currently on back order - so will wait until that arrives before tacking the replacement myself.

The replacement DPF Differential Pressure Sensor arrived today, will be fitting that today, which should resolve that issue.

After bleeding the coolant system a couple of times yesterday, there has been a marked improvement, but the temperature is still rising above 115 Celsius on inclines at 2000 revs and 70 mph. On level roads with revs at around 1200 and speeds up to 50 to 60 mph, the temperatures run up to 105 Celsius and hold there.

The DPF is steady, showing 9 grams soot based upon the Differential pressure sensor, which is of course faulty as it either shows N/A or a high reading of 20 to 30 at when engine is running with the vehicle stationary. The DPF soot level reading is therefore unreliable.

Will update after today's efforts.

John

now then. did the "two o rings on the throttle body connection" prove to be a permanent fix ? I have a similar issue where the throttle body was moveable back and forth by a couple of mm, though there is not much oil residue to speak of. I have also had dpf issues (it went to red with no amber warning and soot levels increase in just a few miles especially with high revs).
I have tried to tighten the throttle body external wire clip and reseat it but not sure if this is enough to cure the leak which I presume I have.
is there anything on the iid tool which would let me know I have a leak, a boost pressure measure perhaps ?

Hello All,

After getting a GAP IID (I've updated firmware and all) last week I've been looking at some live values.
The DPF pressure differential voltage is there, at operating temp idle it shows 0,7xx volt and it goes up with a bit of revving, that seems to be normal.
The DPF pressure differential sensor readings are N/A, even after some time.

In the workshop manual/Exhaust System/TDV8/DPF/Pinpoint test/A6_Functional Check it shows 1 volt=100mbar, 1,5V=300mbar @ 4000rpm.
Does this mean the ECU can convert sensor voltage to mbar?
If so, why doesn't it show?
One could argue the ECU doesn't have to, the voltage readings are enough to determine the flow resistance in the DPF.

In post #1 by 4434Morrison it's mentioned the values of 25V and 20Kpa are shown.
Even with way-off voltage readings it does show pressure values.
So it is possible to see pressure values?
 2012 4.4TDV8
2000 Honda S2000

25v is likley0.25v and maybe the OP calculated the pressure ?
The workshop procedure will also involve the use of a calibrated pressue guage to check voltage against pressure which is the actual way to test a sensor. You could easily ask the technical team at GAP to enable the actual pressure or explain why they can't as they are normaly very helpful and quick to respond. Why do you need this value BTW? 2012 TDV8 Vogue (L322)