Freelander 1 The, I've put my EGR back on!! Thread

[Skinny Mike]

Yes it's true, for various reasons,some of us have put the dreaded and much hated EGR valve back on
In an attempt to see if it has an affect on the 2000rpm judder syndrome, @Nodge68 has re-installed his, with positive results.
Personally,I've been considering putting mine on, as I've put the car back to factory standard as i track down an electrical gremlin.
So the Synergy 2a is off, the battery came off for a good charge, all accessible connectors have been cleaned including autobox, ABS and engine ECU.
Ran the car for a week still without the EGR to let it settle, no faults showing! so I thought in for a penny etc. So this morning, i put the EGR back on, which has been off for around 6 years, and started the car backup.
Well I thought I'd killed it Cough Splutter Chug Chug,nasty noises, bouncy revs, Cough Dies
Thinking about it, I thought, got to be the ecu trying to sort itself out, so started it back up. Started, wobbled a bit,then settled down to 750rpm tick over. Won't bore you with the driving it round at various speeds (with some hair raising losses of power) , stopping starting etc while the ecu and autobox sorted themselves out.
So overall, whats it like?
Quieter but less overall power,although the power band is smoother on acceleration. As for the 2000rpm judder, well its not there at the moment, but its only been one day,and this could be due to the ecu's sorting themselves back out.
So if anybody else wishes to try this and see whether it resolves the 2000rpm judder on more than one car, please post in this ere fred.
Cheers
Mike

 

[Rivo81]

I got rid of mine after about a month of driving with it on and if anything it "seems" like power and pull is actually down with the bypass fitted! I have no hard science but it seems like it had more grunt tackling steep hills in high gears before. The difference doesnt seem worth my while refitting it again though and I prefer the idea of that sludge not choking the manifold etc

 

[Nodge68]

Do have a way to rest the adaptive values stored in the ECUs? Both engine and gearbox ECUs will modify there parameters over time to maximise performance and driveability. I think this is why mine didn't like a disabled EGR.

 

[Skinny Mike]

I suppose a couple of the questions are, does the EGR have enough effect on the ECU to destabilise fueling at 2000rpm. And is it worth having an EGR on and having to strip the manifold etc for cleaning every 6 months or so, dependent on driving style. I did stumble across a Web site the other day that offered a download to delete the EGR out of the ECU program, if you had the relevant equipment to use it. Sounded a bit risky, but who knows? Mike

 

[Nodge68]

I think part of problem with the EGR system on the M47R is we don't know what the ECU does if it's not working. Basically we don't know what or even if the ECU compensates if it's not there. On my D3, the engine ran better without the EGR valves connected to the intake manifold. In that, the ECU compensated perfectly and simply logged a fault code for a colder than expected intake temperature. Obviously if the ECU has opened the EGRs, the intake temperature would increase accordingly. This is what the ECU detected and flagged up as a potential issue. Otherwise the D3 TDV6 ran perfectly without exhaust gas recirculation.
I'm coming to the conclusion that the ECU running the M47R isn't as smart as I would like. I think that removing the EGR throws the fuelling all to cock. This would explain why the running is less than good under normal EGR opening conditions. I don't think that it leans the mixture, as this would simply reduce power. However I think it's messing the timing of the injection or the way the fuel injected. Whatever it's doing, I think it's confusing the ECU, giving the symptoms at 2K Rpm.
So far, mine hasn't messed about since reinstating the EGR.
As for cleaning. I think if the manifold is cleaned annually, that should be good enough. My manifold is in a dreadful state and so has been added to the to do list.

 

[teddywood1]

I have never been a fan of the egr blanking and as for the ron box I had on similar in the early days of owning a td4
around 2004 and yes there was a bit of extra power but all it was doing was putting more fuel through and as the fuel lay in the turbo hoses I think I go through them more quickly and we did not have these new hoses from the likes of dph in those days so it was costly and I was trying everything as I was not used to having a diesel as I never had one before and I was used to things like a 2.9 Granada and a Mondeo sport. but now after a few years I have settled down to a more slower speed but I wish I had more top speed which I am looking into .

 

[Skinny Mike]

Interesting read, http://www.tuneruniversity.com/blog/2012/05/dont-block-or-remove-the-egr-valve-its-saving-you-money/

 

[Nodge68]

I have never been a fan of the egr blanking and as for the ron box I had on similar in the early days of owning a td4
around 2004 and yes there was a bit of extra power but all it was doing was putting more fuel through and as the fuel lay in the turbo hoses I think I go through them more quickly and we did not have these new hoses from the likes of dph in those days so it was costly and I was trying everything as I was not used to having a diesel

How can the fuel sit in the hoses when it's injected directly into the cylinder?

Interesting read, http://www.tuneruniversity.com/blog/2012/05/dont-block-or-remove-the-egr-valve-its-saving-you-money/

Although this web site is talking about petrol engines so not entirely relevent here as
Diesel engines are fueled differently.
However the ECU doesn't appear to compensate for the lack of EGR, at least not quickly. Since reactivating my EGR valve, the 2K miss has vanished, it's much nicer to drive, more responsive and I'm thinking it's better on fuel too.
To me, that makes an annual inlet tract clean, perfectly justified.

 

[Skinny Mike]

but now after a few years I have settled down to a more slower speed but I wish I had more top speed which I am looking into .

If your having trouble with top end speed, check out the MAP sensor, on the left side of the inlet manifold. Replaced mine after some trouble, made a world of difference. Mike

 

[dog-man]

Ever since I did the EGE bypass mod and fitted a Ronbox, my TD4 has been far more responsive and more fuel efficient.
I am no mechanic, but as an owner and driver, I would say that my FL has been performing far better and cheaper since the mods.

 

[Nodge68]

Ever since I did the EGE bypass mod and fitted a Ronbox, my TD4 has been far more responsive and more fuel efficient.
I am no mechanic, but as an owner and driver, I would say that my FL has been performing far better and cheaper since the mods.

A faulty EGR valve will cause poor running and low power, if it's stuck open.
In this instance, removing it is going to give an improvement.
Does yours have a misfire at 2K Rpm on a trailing throttle?
Mine did without a working EGR.
I don't have a Ronbox so can't comment on its attributes.

 

[dog-man]

Never had a misfire in the 4 plus years I have owned it.

TD4 2006. 60000 miles on the clock.

 

[Nodge68]

Never had a misfire in the 4 plus years I have owned it.

TD4 2006. 60000 miles on the clock.

That's lucky. I dissabled my EGR and it started the 2K Rpm misfire straight away.

 

[GrumpyGel]

That document sounded like it related to carburetor (petrol) engines as it appeared the fuel mix was proportional to air rather than injected - but I don't suppose any carb era engines have an EGR. Mind you I suppose even with injectors it needs a proportion of fuel to stop it running to lean so sucking in EGR (oxygenless) gas allows less fuel to be injected.

 

[hd3]

re ..

Interesting read, http://www.tuneruniversity.com/blog/2012/05/dont-block-or-remove-the-egr-valve-its-saving-you-money/

on reading it .. couldn't see that relating to the m47r ..
took note of map/boost data today .. only time it showed a minus boost ( - 0.1 psi / - 0.4 psi ) was at idle
and that could easily be the local atmospheric pressure in effect ..
lite go-pedal pressure on the 'flat' .. or foot-of-go-pedal going 'downhill' .. had no minus effect .. ( boost no less than 0.00 .. i.e. atmospheric psi or thereabouts ) ..

some diesels have an air throttle .. do they not ..
thinking about the freelander 2 td4 .. did some not have a problem with that device ?
some sort of electronic operated gizmo on the air intake ?

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EGR deletion causes misfire at 2k rpm .. :
this be the 1st time i've read about it .. can't find any other posts with this issue ..
noted that Nodge 'n Skinny are both running auto gearbox hippo1 td4's
( which i'm starting to think of like a computer and printer setup
( i.e. 2 computers that need to 'talk' to each other

on google searching ' diesel m47r td4 misfire at 2000 rpm ' .. apart from LZ threads ..
the other results were from bmw drivers .. and the 'issue' came out as 'maf' related ..

i once searched via google for ' bosch maf circuitry '
1 diagram showed a connection to the ecu that was labeled '2000 rpm crossover' ..
( or similar .. it may have been 2500 rpm )
thing is .. i searched again weeks later and could not find the same diagram ..

i did once have a slight misfire at 2000 rpm ..
but only when holding that rpm in neutral .. and with the AC 'on' ..
wasn't very evident at that .. and certainly didn't do it whilst driving ..
some weeks later i sat and listened again and it were gone ..
between .. i'd been using 'diesel rhino' constantly ..
and had used ' contralube-770 ' on some engine sensor connections
( maf / fuel rail pressure sensor / injector plugs )

I did stumble across a Web site the other day that offered a download to delete the EGR out of the ECU program, if you had the relevant equipment to use it. Sounded a bit risky, but who knows?

might be worth looking into further .. if you think the EGR is definitely the cause ..

i can't quite understand how the m47r would know if the EGR be open or closed
apart .. that is .. from knowing the electronic state of the egr vacuum solenoid .. ( open-closed / on-off )
can't quite see the little bit of cooled exhaust gas effecting the a.i.t. sensor
given it is ways upstream from the egr valve ..
and the a.i.t sensor - in - maf sensor earlier td4's .. no chance ..
having written that .. the only way to be sure would be to monitor the .a.i.t. reading ..
and knowing when exactly the egr valve is open or closed ..

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

as for mine .. ( td4 manual box ) the engine ran better the moment i got rid of the egr
particularly from a standing start .. uphill .. .. plus gave improved mpg ..
with the ronbox and pierburg maf .. plus straight thru exhaust backbox .. much much better

maybe my ecu is a quick learner .. ???
thought that ecu 'learning' happened only with the petrol lumps ..
but i don't know .. .. info only from reading some LZ posts
( wouldn't mind knowing exactly how the ecu works 'n how to re-program it )

thought about going for a remap as well ..
but it's got enough torque / bhp as is .. for my liking ..
a wide enough power-band .. suitable gearing for on-road ..
go-pedal response is fine .. no complaints there ..
overtaking power .. no complaints there either ..
engine runs very smooth .. no discernible diesel ' knock '
( it had a tad at lower rpm on acceleration before i started adding diesel-rhino to the fuel )
115k miles on clock at the moment ..

using the max bhp only results in more tyre wear and fuel consumption ..
( not to mention the clutch and other components )
can only imagine adding more bhp via a re-map would be a bit excessive ..

as for the egr valve .. apart from reducing certain emissions ..
it's an engine strangling device .. prone to getting worse over time ..
think i'd rather look into those add-blue devices for nox emissions ..
if it were possible to add one on ..

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

 

[GrumpyGel]

i can't quite understand how the m47r would know if the EGR be open or closed

I've always wonder why there is a MAF telling the ECU how much air is going into the engine - it knows the revs - so it knows how much air is going in - but of course if there's an EGR not all the air is going through the MAF - so the difference between what should be going in and what the MAF says is going in is what gas the EGR is letting through.

I suppose with a turbo there would be more air "squashed" into the cylinders, but that could only be at higher revs. At higher revs, if the ERG was open, would the turbo not just push air back down the EGR to be vented through the exhaust? That might explain loss of power, performance & poor fuel consumption.

The of course, once the fuelling air mixture starts going a bit wrong you get more smoke/soot in the exhaust. This finds its way through the EGR and starts to clog up the plenum chamber/inlet manifold - further reducing performance & consumption.

Then starts a spiralling worsening of the system.

So blanking the EGR & fitting a tuning box may at that point show a marked improvement in performance & economy. However, I would have thought cleaning out the air flow channels & EGR and ensuring all the sensors are giving correct results would also give the same results.

as for the egr valve .. apart from reducing certain emissions ..
it's an engine strangling device

I can't see that. If its not working properly then it will - but not when its working as it should - bit like the fuel pump!


Not wanting the hijack the thread - but my brother's got (had) a Jag XE R-Sport with a 2.0 diesel engine. Its not a small car, but he averages over 50MPG and on a run can get over 70MPG. What have they done to engines/cars to get this level of improvement in fuel comsumption? Those are the figures displayed by the onboard number cruncher - but presumably filling at the pump would confirm its somewhere near these figures.

 

[Skinny Mike]

I've been reading through a couple of books and the only ecu that appears to 'learn' is the auto box tcm. The engine ecu is adaptive, and moves through varying programs, and the ABS is, well ABS! So maybe my TD4 and @Nodge68 will give different results as we have an extra 'learning' ecu in the equation. As for does the ECU know the EGR is not working, yes it's the only fault code mine throws consistently, so it must therefore adapt to it not working.
On the subject of big diesels getting high mpg, I was driving a Jeep wrangler, the bigger one, the other week and when cruising, that was doing 48mpg in 2wd. I thought 'f*ck me` my Grand Cherokee does 31 mpg always no matter what , but I suppose that's constant 4wd.
Mike

 

[Skinny Mike]

re .

as for mine .. ( td4 manual box ) the engine ran better the moment i got rid of the egr
particularly from a standing start .. uphill .. .. plus gave improved mpg ..
with the ronbox and pierburg maf .. plus straight thru exhaust backbox .. much much better

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Ignoring the EGR for the mo, I miss my synergy 2a! Yes it gives better throttle response, yes it gives better mpg, yes it's like sh*t off a shovel. I now have the heart stopping 1 second delay from pressing the pedal to going. Think I've found my electrical gremlin, so hopefully after a bit more testing the Synergy is going back on. Mike

 

[Nodge68]

I've always wonder why there is a MAF telling the ECU how much air is going into the engine - it knows the revs - so it knows how much air is going in - but of course if there's an EGR not all the air is going through the MAF - so the difference between what should be going in and what the MAF says is going in is what gas the EGR is letting through.

I suppose with a turbo there would be more air "squashed" into the cylinders, but that could only be at higher revs. At higher revs, if the ERG was open, would the turbo not just push air back down the EGR to be vented through the exhaust? That might explain loss of power, performance & poor fuel consumption.

The of course, once the fuelling air mixture starts going a bit wrong you get more smoke/soot in the exhaust. This finds its way through the EGR and starts to clog up the plenum chamber/inlet manifold - further reducing performance & consumption.

Then starts a spiralling worsening of the system.

So blanking the EGR & fitting a tuning box may at that point show a marked improvement in performance & economy. However, I would have thought cleaning out the air flow channels & EGR and ensuring all the sensors are giving correct results would also give the same results.

I can't see that. If its not working properly then it will - but not when its working as it should - bit like the fuel pump!


Not wanting the hijack the thread - but my brother's got (had) a Jag XE R-Sport with a 2.0 diesel engine. Its not a small car, but he averages over 50MPG and on a run can get over 70MPG. What have they done to engines/cars to get this level of improvement in fuel comsumption? Those are the figures displayed by the onboard number cruncher - but presumably filling at the pump would confirm its somewhere near these figures.

You're on the right track GG. The engine does know exactly how much air should be going through the cylinders at a given Rpm. The ECU assumes that the engine is a positive displacement pump.
The boost pressure is measured by the MAP sensor, this is needed to calculate how full the cylinders are.
The MAF is there to fine tune the difference between fresh air and recirculated exhaust gas (CO2).
The theory behind recirculation is to reduce combustion temperature at light load conditions. This happens automatically on a petrol engine as they are throttled using a butterfly.
A diesel is at Wide Open Throttle (WOT) all the time, power being generated by adding more fuel. This gives high combustion temperatures, creating Nitrogen Dioxide (NOX). So to help keep NOX in check, an amount of inert exhaust gas (CO2) is fed into the inlet tract. Less Oxygen requires less fuel, giving lower NOX emissions.
It works too but there are side effects. Mostly to do with the actual stuff being fed back into the engine. Diesel contains large numbers of particulates (soot) which clogs up the EGR valve and the intake manifold too. Often there is an amount of oil mist added to the air from the turbo which gets added to the mix. This is what the horrible sticky black goo is that coats everything downstream of the valve.
In theory an engine doesn't need or want exhaust gas fed back into the inlet. For best performance or economy, it's simply not needed.
I think part of the problem with the M47R is the ECU and it's programming. It was obviously designed to run in EGR mode. Removing the EGR throws the ECU into wobbler mode and confuses it. Now it's actually an adaptive ECU so it might be able to map it's self out of wobbler mode, given time. This is a guess, based on my knowledge of other adaptive ECUs.
GG you mentioned the exhaust gas flowing the wrong way. This can't happen as the exhaust side of the turbo will always be at a higher pressure than the intake side. So if a pipe is linked between exhaust and intake side, gas will always flow from exhaust to inlet.

 

[hd3]

( edited 22:23 ) query deleted ..
already found loads online .. with reviews ..