telly-addict wrote:

So I got the remap and had the EGR mapped out.

a remap with EGR delete will greatly improve your situation and remove a point of failure for several common faults. Emissions will NOT be affected as the DPF is still very much in use and MOTs are NOT a worry (speaking from experience).

Just had a quote from SLT of £175 to delete the EGR. 2012 TDV8 Vogue (L322)

Just read the workshop manual and it says the ECU uses the EGR valve during regeneration. It opens during overrun as the throttle plate is partially closed during regens and this stops excessive engine braking. It also uses the EGR to help regulate the intake air temperature (I've seen both these on the GAP IID live values BTW) . It would need a very clever remap to delete the valve and if you physically blanked it you would have issues. Also there are other descriptions of how the system carefully controls the burn to specific temperatures and as indicated the EGR valve will likley be part of this. A clever way to reduce intake fouling would be a remap that ran a lower % of EGR gasflow on light throttle / low power but still operated normally during regeneration. I know on some cars they fit restrictor plates that allow just enough egr flow into the intake to not throw a CEL but it's less than stock so fouling is reduced. 2012 TDV8 Vogue (L322)

Ramblin Man wrote:

And please confirm that you fabricated your own EGR blanking plate.

Thanks.

Yes I did indeed make my own blanking plate with 2mm steel sheet

Oh and it's a Quantum map. Cam

2011 TDV8 Vogue in Stornoway Grey

JayGee wrote:

Just read the workshop manual and it says the ECU uses the EGR valve during regeneration. It opens during overrun as the throttle plate is partially closed during regens and this stops excessive engine braking. It also uses the EGR to help regulate the intake air temperature (I've seen both these on the GAP IID live values BTW) . It would need a very clever remap to delete the valve and if you physically blanked it you would have issues. Also there are other descriptions of how the system carefully controls the burn to specific temperatures and as indicated the EGR valve will likley be part of this. A clever way to reduce intake fouling would be a remap that ran a lower % of EGR gasflow on light throttle / low power but still operated normally during regeneration. I know on some cars they fit restrictor plates that allow just enough egr flow into the intake to not throw a CEL but it's less than stock so fouling is reduced.

Sorry I should have made it clear in that extract from the WM that the regulation of intake temperature only happens during the regen process and is necessary to prevent damage to the DPF and I don't think the EGR is used to regulate intake temps during normal driving. Did the tuner say to physically blank the EGR as if the throttle plate is still closing on overrun in normal driving it suggests the ecu is still thinking there is an EGR valve. No fuel is burnt on overrun so if the EGR opens it's not contributing to soot and is just an economy feature but as you say a bit of engine braking can benefit drivability. How many miles have you done with this mod and have you monitored the regen frequency and EGR temps during a regen? 2012 TDV8 Vogue (L322)

Just weighing in here based on my experiences…

I have a 4.4 TDV8 which I have had the EGR valve blanked and mapped out. I debated this for a long time due to the varied opinions on the issues it could cause. I researched as much as I could and, while I am no mechanic or car expert in any way, I felt it was ok to proceed. My understanding was that the EGR valve is used to reduce the “burn temperature” to reduce NOx at the cost of more soot, and also to help reduce the exhaust temp following DPF regenerations.
The theory was that the DPF regen frequency would reduce due to less soot being produced, and as these cars are designed to operate in far hotter countries, there was less of a need to “help” cool the exhaust.

The final nail in the coffin for me was finding a gunked up plenum chamber.

JayGee wrote:

Sorry I should have made it clear in that extract from the WM that the regulation of intake temperature only happens during the regen process and is necessary to prevent damage to the DPF and I don't think the EGR is used to regulate intake temps during normal driving. Did the tuner say to physically blank the EGR as if the throttle plate is still closing on overrun in normal driving it suggests the ecu is still thinking there is an EGR valve. No fuel is burnt on overrun so if the EGR opens it's not contributing to soot and is just an economy feature but as you say a bit of engine braking can benefit drivability. How many miles have you done with this mod and have you monitored the regen frequency and EGR temps during a regen?

Ffrr-lover wrote:

Would I recommend others remove their EGRs? Due to the varied opinions on this subject by others far more knowledgable then me… I cannot. That would need to be decided by yourselves based on your own research.

Would I do it again? Absolutely and without hesitation. I love the earlier comment about not feeding the engine its own excrement, and it sums my feelings up perfectly.

 Cam

2011 TDV8 Vogue in Stornoway Grey

I have to say that as mine's not far off 150k miles and the price of diesel is not going down the argument for preserving the DPF and increasing mpg is quite persuasive. How much did Quantum charge and was it as part of a performance remap or a standalone thing? 2012 TDV8 Vogue (L322)

How you duys solve/think about next things:
1) Did you install a separate blow-up valve for turbos? Because EGR valve play also blow-up valve role on many diesel engines, incl. 4,4. When you suddenly release accelerator pedal after high performance, EGR valve open immidietly and release the overpressure back to exhaust system via EGR.
2) Is this remapping takes in mind different air flow via MAS sensors? Now, without EGR you have higher air flow from outside due no additional air from EGR valve. Injection should be corrected according that new different airflow as well.
3) What you thinking about higher combustion temperature in combustion chamber, how this effects to pistons and turbos in long term?

IMHO none of those make any significant difference.... Pete

__________________________________________________
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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-

They're all valid points though - ones that were taken care of in design, unlikely to be thought of by many of the 'remappers'. Some of them may well take a while to develop issues, some may contribute to know issues like inlet manifold splits earlier than otherwise.

jaguar3 wrote:

How you duys solve/think about next things:
1) Did you install a separate blow-up valve for turbos? Because EGR valve play also blow-up valve role on many diesel engines, incl. 4,4. When you suddenly release accelerator pedal after high performance, EGR valve open immidietly and release the overpressure back to exhaust system via EGR.
2) Is this remapping takes in mind different air flow via MAS sensors? Now, without EGR you have higher air flow from outside due no additional air from EGR valve. Injection should be corrected according that new different airflow as well.
3) What you thinking about higher combustion temperature in combustion chamber, how this effects to pistons and turbos in long term?

JayGee wrote:

I have to say that as mine's not far off 150k miles and the price of diesel is not going down the argument for preserving the DPF and increasing mpg is quite persuasive. How much did Quantum charge and was it as part of a performance remap or a standalone thing?

Thanks. Could do with a power decrease on mine - wonder if they can map out the 2nd turbo  2012 TDV8 Vogue (L322)