Good to hear!
EGR Delete
- Thread starter Loz
- Start date
-
- Tags
- delete egr egr cooler egr delete
I wonder what Oli @BognorMotors has to say about deleting the EGR
unlikely as its the SCR and DPF that deal with that.
Not something we would get involved in or endorse
Sorry what a silly question I asked
As mentioned earlier by Daffy, the EGR is to reduce combustion temperature. This is to reduce NOx. I've experienced a few vehicles running with EGR blanks and in general they take longer to warm up and can be jerky at low speed or light throttle application. Fuel consumption has increased in every case too.
For vehicles equipped with DPFs, the EGR is also used during the regen process and I'm pretty sure the main companies that do remaps always leave the EGR functioning for DPF equipped vehicles for this very reason too. I'm sure that really friendly chap in Barnoldswick would explain if you phoned him
For vehicles equipped with DPFs, the EGR is also used during the regen process and I'm pretty sure the main companies that do remaps always leave the EGR functioning for DPF equipped vehicles for this very reason too. I'm sure that really friendly chap in Barnoldswick would explain if you phoned him
I know this has been dealt with by mooncat but I just had to comment, the EGR introduces exhaust gases into the combustion charge, as they have already combusted they have a very low oxygen content. They are introduced into the inlet they effectively reduce the volume of (Oxygen rich) clean air in the combustion charge. Less oxygen means less burn and thus lower temperatures.
I haven’t studied the cooling system on the Euro 5 or 6 T6 but there will be multiple cooling systems all working independently with the liquid cooled ones using the same coolant.
You are correct that the charge air cooler cools the intake air as cooler air is more dense and makes a bigger bang so the effect of the turbocharger has to be dealt with, you are also correct that the EGR has a cooler to cool the exhaust gas from around 675’C to around 150’C at full power, the reason for the cooling is to try to minimise the effect on the charge air temperature.
If I was deleting the EGR I would use a shim in place of a gasket as above but IMO there are other issues that need to be dealt with, I certainly wouldn’t want to try it on my own van..
*FYI the temps given above don't directly relate to a T6 but I’m willing to bet they aren’t far out.. Apologies for the lecture but its a bit of a specialist subject of mine
I’m not an expert on ECU’s or the intricacies of VW EGR systems but here’s my take on it as an Engineer and Mechanic (non auto):
In a so called EGR ‘delete’ situation - If the exhaust gas is not re-circulated through the EGR system to the combustion chambers then the inlet charge will be made up with all clean air. In this case the mass air flow meter will register more air and deliver more fuel. More power available but more fuel consumption
More charge air will put a greater load on the charge air cooler and if it’s capacity to cool is exceeded the performance will drop due to a less dense charge.
Diesel engines in particular benefit from a very short scavenge period where both inlet and exhaust valves are open at the same time at the top of the exhaust stroke, this removes unburnt gases ready for the fresh charge. To me the principle of EGR does the complete opposite and hinders combustion.
Obviously the auto industry has to meet regulatory requirements and we’d like to think has the top minds and computer modelling to produce the best power units possible.
This apparently is not the case.
In a so called EGR ‘delete’ situation - If the exhaust gas is not re-circulated through the EGR system to the combustion chambers then the inlet charge will be made up with all clean air. In this case the mass air flow meter will register more air and deliver more fuel. More power available but more fuel consumption
More charge air will put a greater load on the charge air cooler and if it’s capacity to cool is exceeded the performance will drop due to a less dense charge.
Diesel engines in particular benefit from a very short scavenge period where both inlet and exhaust valves are open at the same time at the top of the exhaust stroke, this removes unburnt gases ready for the fresh charge. To me the principle of EGR does the complete opposite and hinders combustion.
Obviously the auto industry has to meet regulatory requirements and we’d like to think has the top minds and computer modelling to produce the best power units possible.
This apparently is not the case.
You are correct in much of what you say in that the whole reason for the EGR being there is to hinder combustion, you won’t see more power without it as there is no exhaust gas going into the cylinders where there is a call for high power output (remember it hinders combustion so this would be counter productive)
As already mentioned by someone above the purpose of the EGR system is to reduce NOx levels at certain engine speed/loads to meet emissions criteria.
As to the best minds producing the best power units, one thing is very clear when you talk to these people - that is, the engine would be very different if it were not for emission legislation, not only current but also future as our engines are also field trial units in many ways.
I agree with the theory but when, years ago, I blanked the EGR on a BMW engined Landrover, it instantly became more free revving and smoother, nicer to drive and (subjectively) faster. As somebody else said, it felt like it had just quit a 60 a day smoking habit. It also took longer to warm up.
I can only conclude that all the carbon build up stopped the valve operating properly, so letting exhaust gases into the inlet manifold when under full throttle, however I'm not an expert.
That engine didn't have a dpf or the complex electronics that our T6's have, and I won't be touching my van's EGR valve.
US9260995B2 - Cyclone particulate filtration for lean burn engines - Google Patents
Provided is a particulate filtration apparatus for removing combustible and noncombustible particulate matter from a lean burn engine exhaust gas stream containing particulate matter. The apparatus comprises a cyclone body with a roughened surface on the inner walls designed to trap and...
patents.google.com
The problem is it adds cost and doesn’t have the bells and whistles that sells vehicles.
At service time they can be manually cleaned, chemical flushed or disposable cartridge.
I think that is more DPF than EGR as it deals with particulates, the EGR is to reduce NOx which is a gas.
Something similar has been trialled on buses to achieve a later emission standard than their design allows, however they are maintenance heavy as they can’t be cleaned without specialist equipment (read expensive)
interesting thread this.
It’s not a theory, its how it works for the vast majority of Euro 5 & 6 diesel engines, unfortunately its not going to get easier with ever tightening emissions legislation almost yearly now.
Yes, this will almost certainly be my last diesel engined vehicle.
Funnily enough I have just taken delivery of a 2.0ltr Tiguan with a petrol engine, thats someone who has been a huge advocate of Diesel engines in passenger cars for the last 20+ years and owned nothing else.
I've been out of the diesel engine industry for over a decade now - what I can say however is that the company I worked for went through as many emission regulation changes as possible before adding a cooled EGR system. The main reason for not wanting to go along the EGR route was not regarding carbon build up in the inlet manifold but the issues around taking heat out of the exhaust gases before they were fed into the inlet manifold. Once you've absorbed that heat into the cooling system you have to get rid of it.
Was Involved with tuning Peugeot’s many moons ago deleting egrs and getting rid of the additive injection and remapping and tbh yes the power increases with remapping were great and a lot of the time improved mpg but when the egrs were deleted that’s when the problems came with lots of top end damage mainly due to increased combustion temperatures, so until someone has done theirs on a t6 and run it for 50,000 miles at least I’ll be keeping mine lol
