markieboy123

Active Member
Hi All,

looking into possible modifications on my L322.
see lots of information on the Tinternet about blanking the EGRs.
I have the 3.6 TDV8 and wondered what the general opinion was ?
Blank them or leave alone.
is it preventive maintenance or just to increase fuel economy?
Appreciate the knowledgeable views on here and would appreciate you guys take on it
 
Personally, if you maintain it as part of servicing then i don't see a problem. Don't know about mot implications
 
As much as many do it (on the older engines).
With all the monitoring that the modern 1s do I am not sure if its possible or if the electrickery would throw a fit. So it may not be such a simple job as some older engines to actually do it.
It is an MOT failure, but of course they wouldnt see it under all the engine covers;).

I would leave well alone personally:).

J
 
Don’t think the MOT tester can remove the engine cover to see if the egr has been removed.
I am happy to continue do regular oil changes but wondered what the general opinion was
 
Dont think egr works at idle, especially before the stat opens.
If there are no sensors in the exhaust then the car cannot possible know if you have blanked it or not.
 
Dont think egr works at idle, especially before the stat opens.
If there are no sensors in the exhaust then the car cannot possible know if you have blanked it or not.
Newer ones have a position sensor at least, presume that would set a fault/engine light if missing
 
Newer ones have a position sensor at least, presume that would set a fault/engine light if missing

300 tdi egr used to have a throttle position sensor, I think that to stop the egr opening when at idle, this was on pre edc engines.
Same set up is used on the Ve pump on volvo penta engines to operate the white smoke limiter, which does not work as advertised!
 
On the TDV8 4.4 documentation I have there is 3 pages of DTC for the EGR. They mention EGR gas temp sensors, maybe it knows if gas is flowing or not;). will it throw an engine light? I wouldn't be surprised;). Is the 2010 3.6 the same I dont know;).
And yes it does operate at idle when up to temp.

As said I would leave alone:D.

J
 

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If there are no sensors in the exhaust then the car cannot possible know if you have blanked it or not.

The ECM is smart enough to know the EGR is blanked.
The the EGR routine goes like this.
The ECM opens the EGR valve and monitors the decrease in air flow through the MAF, reducing the fuel injected as a result of the lower oxygen content. However the ECM also monitors the intake temperature, which it expects to see a rise in intake temperature as hot exhaust gas warms up the intake air. This temperature rise is used to provide fine control of the fuel, however it also serves as a secondary function of checking that the EGR system is still functional. Blanking the EGR on a monitored system will put the MIL on, which will then cause an MOT failure, unless the EGR temperature tell tale is mapped out of the ECM.
 
The ECM is smart enough to know the EGR is blanked.
The the EGR routine goes like this.
The ECM opens the EGR valve and monitors the decrease in air flow through the MAF, reducing the fuel injected as a result of the lower oxygen content. However the ECM also monitors the intake temperature, which it expects to see a rise in intake temperature as hot exhaust gas warms up the intake air. This temperature rise is used to provide fine control of the fuel, however it also serves as a secondary function of checking that the EGR system is still functional. Blanking the EGR on a monitored system will put the MIL on, which will then cause an MOT failure, unless the EGR temperature tell tale is mapped out of the ECM.
As above, the EGR on the PUMA engined Defender certainly cannot be blanked or disconnected without the MIL light coming on, it has to be mapped out which is technically illegal and an MOT failure. There is talk over here of extending the CT (MOT) to allow the ECU to be interrogated and compared to a standard map which if it happens will catch many people out.
 

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