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Discussion Starter #1
As title, really. There's lots of talk of blanking the EGR, but (and yes I've tried searching) why do it?
Is it to overcome the problems of a sticky or malfunctioning EGR?
Are there performance or economy benefits?
Does a healthy EGR aid cold running or part throttle or something?
Are there downsides? - Turbo temperature or life perhaps?

Thanks.
 

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So we can enjoy hot summers once again.
Blanking it will stop exhaust gases recirculating back in engine - to lower emissions.
 

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The amount of NOx an engine produces is a function of both the temperature, and the amount of oxygen available. By recirculating exhaust gases, there is less free O2 available (as it's already been used for combustion).

At the end of the day, Diesel exhaust is full of soot. Diverting that soot back into the engine is always likely to lead to reliability issues.
 

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EGR blanking along with DPF bypassing has been going on a while now, very rarely have I heard of side affects or problems caused as a result of either procedure.

Generally speaking after either procedure (assuming its done correctly and ECU is mapped accordingly!!!) the car should be more reliable, have more power and be more economic..

Don't forget EGR valves and DPFs are made necessary by new worldwide emission laws not out of preferance by car manufacturers.
 

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As title, really. There's lots of talk of blanking the EGR, but (and yes I've tried searching) why do it?
Is it to overcome the problems of a sticky or malfunctioning EGR?
Are there performance or economy benefits?
Does a healthy EGR aid cold running or part throttle or something?
Are there downsides? - Turbo temperature or life perhaps?

Thanks.
people blank it off maily due to cost of putting a new one on, others because the are having it remaped

the TURBO as nothing at all to do with egr or how it works, so dont even start worrying about that one
as said allready its just a reburn system that reburns exhaust at times when engine isnt needing power, ie cruising

my old 156 had it blanked of and apart from a slight flat spot in second gear there where no problems and it passed every mot.......a remap would have sorted the flat spot but i wasnt that bothered

Gary
 

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they dont have DPFs, no, think they just have good old fashioned cat. However seeing as this thread is about EGR valves, yes, they do have one.
 

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I blanked the egr valve off on my 8 valve 1.9 jtd 156 and it made a fair improvement especially to the light throttle response and fuel consumption, it showed an improvement of about 5mpg
The whole point of the egr valve is as has been said to reduce nitros oxide or dioxide emissions by reducing the combustion efficiency which must waste fuel.
Before I blanked it off it was clean and working properly so it wasnt just masking an existing fault.
I used a plate bought on ebay for about £3 and it was well worth it..

The only slight down side is that due to the exhaust gas not flowing through the cooler the car did take a while longer to get upto temp on cold mornings.
 

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where can i get the engine check light turned off if i blank mine?
You need to get the car remapped, your ECU monitors the emissions and with the EGR blanked the engine will produce different figures (thus causing the MIL light) ... a good remap will change the expected values such that your light won't come on
 
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if you can live with the mil light pul the plug off or blank it off and go for it once you've got an mot!!
 

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My 156 was a 2004 and I think a cf3 so it didnt bring the light on, my 2006 159 did bring the light on before it was remapped, so depending if yours is cf3 or cf4 it might come on, the egr doesnt have any flow sensors but the ecu some how works out if there is a flow through the egr by looking at readings from the maf and map sensor
 

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Discussion Starter #14
Interesting thanks - so it's an emissions measure. How ridiculous that it reduces tailpipe emissions by making combustion less fuel efficient. Another piece of genius legislation. I can see how part throttle economy would be improved by blanking it, if that's when it's active.
 

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Discussion Starter #15
Being a higher CO2 16v 1.9 mine is a cf3 is it? I know the later GTs (55 onwards?) had a 'modificato' engine management and different injectors - is this cf4?

So perhaps by just unplugging my EGR I can get some of the part throttle benefits AND not have the MIL light on...
 

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your engine runs cooler without it and cf3 engines DO throw a fault in ecu when they are blanked even when they are still plugged in
 

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Hello,

I want to blank my EGR off on my 2009 2.4 159 and I have noticed that you can get a full blank, or a blank with holes? I assume the one with the holes is to reduce the flow and a full blank is a "full Blank".

Is a full blank is better? :confused:

Will I need a remap after blanking?

If I don't remap and the blank puts the car into limp mode (I've been told this may happen), will just simply removing the blank take the car out of limp mode?

Best Regards
Matt
 

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one with holes allows a bit of flow, simply for the purposes of not throwing up engine light.
Full blank is best, but will throw up engine light
No need for remap with either option. Although remap can delete the egr from the computer, then a full blank without engine light can be achieved.
The car won't go into limp mode with any combination.
 
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