[paragsachania]

Originally Posted by DerAlte

Also, EGR doesn't affect FE - it is exclusively for NOx reduction. If EGR is not working, you might get better FE (don't try it though).

^ and that is precisely true that recently one of my relatives complaining of poor FE in his Indigo CS took it to an FNG and that fella simply introduced a metal sheet in the EGR valve and blocked it for good.

The results: Definite improvement in FE Numbers
The verdict: Temporary workarounds and momentary pleasure of having an impression that the problem is solved.

Like you mention, its the sensor position of the EGR which acts as a signal to the ECU, just like the Throttle Position Sensor, Idle Air controller sensor which mostly works based on the Min-Max voltage range proportional to the valve opening.

A resistance test between Signal-Ground and terminals with Lowest and Highest valve opening can also confirm the functioning of the EGR.

[el lobo 6061]

EGR is technologically good as it helps in reduction of NOX. But our fuel & air quality coupled with harsher environment plays havoc with EGR system.

Its better to disable EGR via ECU remap. In 1.6 TDi you can easily gain 6 BHP by disabling EGR but you do pollute more.

[pcpranav]

Hi,

vehicle: Xylo E6 (mEagle)
ODO : ~92000 KM (3.5yrs)
work: cleaning of EGR
when : in Mar'14
where: MMASS

Few months back I asked directly the MMASS to clean EGR valve. Generally they dont do such work unless there is any specific complaint of vehicle. In my case, I didnt have any issue, simply wanted some cleaning!

After this activity, I didnt notice any change in performance - neither +ve nor -ve.

some pics taken during the process:













I believe the inside of compartment where EGR fits will anyways get carbon soot deposits ! It was gently cleaned using a cloth, without any other liquid. The EGR valve was cleaned using Petrol.

Xylo uses Padmini VNA's EGR valve, which looks just similar to that "Drop Type" model as shown on http://www.padminivna.com/egr.html

Interestingly, while fitting it back, the bolts didnt fit well, and they had to again 'thread' the area, which took a very long time.

regards,

[amitpunjani]

Yesterday I got EGR system cleaned of my Sx4 at MASS Now EGR was cleaned by injection of some additives from the opening of EGR valve. It wasn't done conventional way by opening the whole unit of EGR. Prior to cleaning of EGR engine was also changed. Now I have two major concerns

Is this the rite way yo clean EGR valve with additive and also is there a possibility additive could have mixed with engine oil and harm the engine

[a4anurag]

Originally Posted by amitpunjani

Yesterday I got EGR system cleaned of my Sx4 at MASS Now EGR was cleaned by injection of some additives from the opening of EGR valve. It wasn't done conventional way by opening the whole unit of EGR. Prior to cleaning of EGR engine was also changed. Now I have two major concerns

Is this the rite way yo clean EGR valve with additive and also is there a possibility additive could have mixed with engine oil and harm the engine

I guess it is possible seeing these two videos.

https://www.youtube.com/watch?v=00GyC9ml0iw

Another relevant one:

https://www.youtube.com/watch?v=gOGjAQHVeCc

Seems to be easy but slightly tricky. I'll try this if I can get hold of the product (Bardahl).

Note: Can you find out what MASS has done and how?!

If it is the same procedure then we can do a DIY.

If the above method was followed (additive added in fuel tank) then there is no harm to the engine or the engine oil.

Anurag.

[::CMS::]

EGR Delete will definitely give an improvement in performance and FE but at the cost of environment pollution. It can be done in the ECU map but there are chances that the valve may get open partially to pass the soot through due to the air pressure, so a permanent solution is to block it with a metal plate. It has to be done at both levels for a permanent EGR delete.

[a4anurag]

Originally Posted by ::CMS::

EGR Delete will definitely give an improvement in performance and FE but at the cost of environment pollution. It can be done in the ECU map but there are chances that the valve may get open partially to pass the soot through due to the air pressure, so a permanent solution is to block it with a metal plate. It has to be done at both levels for a permanent EGR delete.

Exactly and IMO not advisable at all.

If at all low power bothers a driver then better to do a remap or buy a powerful car.

Removing / blocking the EGR completely will have that car failing in emission test!

Anurag.

[amitpunjani]

Originally Posted by a4anurag

I guess it is possible seeing these two videos.



Note: Can you find out what MASS has done and how?!

If it is the same procedure then we can do a DIY.

If the above method was followed (additive added in fuel tank) then there is no harm to the engine or the engine oil.

Anurag.

Hi Anurag,

Certainly the procedure, can't be done DIY. A chemical by BG Products was used along with the high pressure of compressed air and the car was revved to about 3,000 RPM. Their was a abit of knocking sound as well from the engine during the process.

From the exhaust there was a lot of Black smoke and some times white smoke as well.

The entire process took about 15-20 mins. I'm not sure... how useful this process in comparison to dismantling of EGR system, but let me tell you there is remarkable improvement in Engine. It feel less harsh and turbo kick is bit early than 2,000 RPM.

Amit

[tikku.dk]

Originally Posted by amitpunjani

From the exhaust there was a lot of Black smoke and some times white smoke as well.

Amit

Revv your vehicle to redline so that the soot accumulated in exhaust gets cleared.BTW EGR cleaning should be done by dismantling EGR and intake manifolds also to be cleaned. You will have a intake manifold filled with carbon

[a4anurag]

Originally Posted by tikku.dk

Revv your vehicle to redline so that the soot accumulated in exhaust gets cleared.

Which ideally is the italian tune-up procedure. But that suggests to revv the engine in all gears while on the move.

I keep doing it every 2K kms.

Anurag.

[interc00led]

Note from Mod: This discussion has been split into its own thread from its original location.

Originally Posted by lurker

Justin, the reasons are very simple. Just go methodically. Timing chain problem was due to long oil change interval. But engine getting clogged up with gunk is due to EGR. But these events can also happen simultaneously as well. In most turbo diesel engines including trucks fitted with EGR valves, this will be a problem.

Unless they can proactively resolve issues by opening and cleaning engine intake manifold ever 30,000 kms. Clean EGR valve every 30,000 kms. Change oil (for mineral every 5K and synthetic every 7K) in light of Indian city driving conditions. (it's not possible to drive above 100 kmph at steady throttle at all times in India, so that EGR valve remains closed).

EGR valve opening-closing is not exactly dependent on vehicle speed but load. Under moderate cruising speed, the egr valve will open. It closes when the rpm is too low or high or under heavy acceleration when full power is needed.

Once the EGR valve gets clogged (assuming that the ports block and not the valve itself ) after 60k kms then there is effectively no mixing of exhaust gases with intake, no?

The mjd has an egr cooler with ports and a bend which gets clogged over a period of time and reduces the amount of exhaust gases going into the intake.

[lurker]

Originally Posted by interc00led

It closes when the rpm is too low or high or under heavy acceleration when full power is needed.

Think again. What is the purpose of EGR. Because of newer pollution control norms being foisted upon car manufacturers, this is one of their primary solutions to make exhaust emissions compliant with Euro IV, BSIV.

Basically exhaust gasses which have unburnt fuel is again recirculated back into the engine so that carbon emissions can be minimized. This also means a hotter running engine, because when the EGR works aka when the valve is open the engine is sucking in hot, dirty, carbon laden air back through the intake. This may minimize emissions but is obviously bad for the engines.

So EGR will close only when fuel is at leanest and emission is most minimum. That would mean in a modern CRDI a steady 70-100 kmph@5th or 6th gear without any increase or decrease in acceleration.

[interc00led]

Originally Posted by lurker

Think again. What is the purpose of EGR. Because of newer pollution control norms being foisted upon car manufacturers, this is one of their primary solutions to make exhaust emissions compliant with Euro IV, BSIV.

Basically exhaust gasses which have unburnt fuel is again recirculated back into the engine so that carbon emissions can be minimized. This also means a hotter running engine, because when the EGR works aka when the valve is open the engine is sucking in hot, dirty, carbon laden air back through the intake. This may minimize emissions but is obviously bad for the engines.

So EGR will close only when fuel is at leanest and emission is most minimum. That would mean in a modern CRDI a steady 70-100 kmph@5th or 6th gear without any increase or decrease in acceleration.

You have got the basics wrong. EGR helps to meet the NOx emissions and not the CO&HC emissions(Catalytic converter is there for this job).
NOx forms at high temperatures and EGR lowers the peak combustion-chamber temperature thereby preventing the formation of NOx.

Yes, I agree that the particulate matter from the egr can cause engine wear but most of it is burnt within the combustion chamber itself and whatever passes past the piston rings get into the engine oil and the modern engine oils are designed to retain/hold it.

Contrary to your statement->Actually, when the engine is running lean(diesels always run lean- here I am referring to relative ratio), the core combustion-chamber temperature will be very high(I am not talking about the exhaust gas temperature here).

[a4anurag]

Originally Posted by interc00led

It closes when the rpm is too low or high or under heavy acceleration when full power is needed.

Originally Posted by interc00led

EGR helps to meet the NOx emissions and not the CO&HC emissions(Catalytic converter is there for this job). NOx forms at high temperatures and EGR lowers the peak combustion-chamber temperature thereby preventing the formation of NOx.

to both the points!

Originally Posted by lurker

Think again. What is the purpose of EGR. Because of newer pollution control norms being foisted upon car manufacturers, this is one of their primary solutions to make exhaust emissions compliant with Euro IV, BSIV.

So EGR will close only when fuel is at leanest and emission is most minimum. That would mean in a modern CRDI a steady 70-100 kmph@5th or 6th gear without any increase or decrease in acceleration.

After reading our post, I thought why not check what the EGR does in reality at certain speeds on the move.

What I did was, asked my friend to take screen shots of the data when I drive.

On a clear road, in 5th gear tried the following:

1) Kept the car cruising at 60 kmph;
2) Kept the car cruising at 80 kmph;
3) Kept the car cruising at 100 kmph and
4) Under acceleration from 80 kmph to 100 kmph.

I wanted to see the reading at these speeds and also to see if the valve is 'Open' or 'Close'.

1)


2)


3)


4)


Conclusion:

• The EGR remains open most of time depending on the throttle position (See Pedal D & E).
  
  
• Under acceleration when the engine is producing power, the EGR valve closes so that the unburnt gases do not enter to reduce the output! hence we see the black smoke at this point.
  
  
• When the car is cruising, the EGR valve is open so the gases/emissions is under control (NOx). AFAIK, the NOx parameter will fail if checked when revving the engine due to closing of the EGR valve.

What say guys?

EDIT: The car in question here is my Swift ZDi

[lurker]

Originally Posted by interc00led

EGR lowers the peak combustion-chamber temperature thereby preventing the formation of NOx.

In BSIII engine, there was no EGR and some Toyota Qualis and Innova which do not have it are running fine even today without opening the engine.

Yes, I agree that the particulate matter from the egr can cause engine wear but most of it is burnt within the combustion chamber itself and whatever passes past the piston rings get into the engine oil and the modern engine oils are designed to retain/hold it.

People who have removed EGR have gained 3 km/L in England. Second the engine runs better on fresh air and you even do not have to change engine oil that frequently. So that lesser crud thrown back into the environment. EGR gains are only theoritical and only in the initial phases before sludge cakes up inside engine and makes every little gain earned through EGR immaterial.

Contrary to your statement->Actually, when the engine is running lean(diesels always run lean- here I am referring to relative ratio), the core combustion-chamber temperature will be very high(I am not talking about the exhaust gas temperature here).

there are people who have kept a sensor on EGR so that they get a notification on when exactly the damn EGR closes. Firstly it doesn't close that frequently, and then when it builds up sludge it doesn't close ever at all.