Trying to understand why many seem to want to turn off EGR only.

Is this to avoid the mechanical issues with clogged intake dt EGR function only, or has turning off EGR in itself a performance impact?

With my EGR disabled, I got no performance gain, but my intake is now super clean, and my oil won't be getting so contaminated. Before disabling the EGR, my inlet manifold was a mess, and it only had 6000kms on the engine.

The reason might be a price of a new EGR. And problems that might show up again after short time.

Ok, thanks.

And then the reason why one would alter the EGR map in a tuning context, that would be to let in more fresh air at an earlier stage of throttle to improve combustion?

Basically by disabling the EGR you get three things.
First- Clean air intake, no oil contamination.
Second- more ''fresh'' oxigen and less exaust gas with almost no oxigen.By more oxigen and less air temperature (because EGR gases are red hot and makes the intercooler work even harder) you get more fuel efficiency which gives you more power.
And Finally third- no more potential problem and limp mode because of EGR possible problem.

Thanks Major! Very educating and one piece of the puzzle in place for me.

major_bvv wrote:Basically by disabling the EGR you get three things.
First- Clean air intake, no oil contamination.
Second- more ''fresh'' oxigen and less exaust gas with almost no oxigen.By more oxigen and less air temperature (because EGR gases are red hot and makes the intercooler work even harder) you get more fuel efficiency which gives you more power.
And Finally third- no more potential problem and limp mode because of EGR possible problem.

The engine will be hotter because the more oxygen that is present the better the combustion so therefore hotter egt. I don't think the gases from egr go through the intercooler to be honest.

The only adverse affect I have is that the engine timing is more advanced because of the egr gasses are not being burned therefore the soi needs retarding. My engine sounds very noises like pinking in a petrol engine. I have citroen xsara picasso with egr blanked out and a Celtic tuning economy map that disables egr in software so no mil.

However the engine is very noisy sounds like a tractor lol, but better response more power and a cleaner air intake. My exhaust isn't so sooty inside either.

Any solutions to the timing aspects to bring it in line with the egr gasses missing?

Gases from EGR don't go throught Intercooler, but they go to the engine so they affect engine smooth work. WIth EGR working you have hotter air in your engine with less oxigen which means less combustion with more fuel then needed.THAT means OVERHEATING your engine and turbo not because of more combustion but because of LESS OXIGENEand unneeded fuel and poor efficency. GET IT ?
Also for your issues with EGR on your car i have a solution, but will keep it for me.

major_bvv wrote:Also for your issues with EGR on your car i have a solution, but will keep it for me.

Oh, you are so super-cool! :clap: :mrgreen:

EGR is intended for lowering NOx emmissions by LOWERING COMBUSTION TEMPERATURES at low/middle torque demands from idling to up to approx. 3k rpm (depends on the engine type).

When on WOT, EGR is fully closed, and has no inpact on combustion or performance.

That's it.

In your post you have only one true thing EGR was invented only for ecological reasons. But EGR works directly AFFECTS engine normal work. In addition -the EGR ALSO closes no matter what rpm you are when hitting the full throttle. DID YOU KNOW THAT- OR NOW I'm mega turbo,hyper,giga cool.
Now second- you are trying to tell me that EGR gases are cooling down your engine- thats a piece of crap. Why you have EGR COOLER than? Also from when exhaust gases (250-350 degrees celsius depending on model and engine type) are cooler than the air through the intercooler ( 20-35) ?
Don't try to make me believe what you think or what you have heard anywhere. Give me science.