EGR should we all be more concerned

[Greg Roles]

[Greg Roles]

Oh and I've simply pulled the plug on the valve to see what happened, and it threw up an error code, but the car felt a bit gutless, so it obviously went onto some sort of power limiting safety map. Had to reset it all via Vag Com.

[gldgti]

not exactly what you want to hear is it?

it really seems that the biggest obstacle for diesels is nitrous oxide output - has been the case for a long time now. just think, if it werent for the nitrous emissions, the factory setup would likely come without a DPF, EGR, or anyhting like that. just run excess air.

back in the day when the mk1 diesel golf came out with the 50hp 1.5l engine (and 1.6, and 1.6TD) they were EXEMPT from the nitrous emissions test because they performed so well in all the other emissions tests (unburned hydrocarbons, CO2 (good fuel efficiency), CO, etc.

they figured back then that if the car could get 4.7l/100km around town and 5.5l/100km on the hiway, it was automotically good for the environment....i would generally agree.

[gldgti]

not exactly what you want to hear is it?

it really seems that the biggest obstacle for diesels is nitrous oxide output - has been the case for a long time now. just think, if it werent for the nitrous emissions, the factory setup would likely come without a DPF, EGR, or anyhting like that. just run excess air.

back in the day when the mk1 diesel golf came out with the 50hp 1.5l engine (and 1.6, and 1.6TD) they were EXEMPT from the nitrous emissions test because they performed so well in all the other emissions tests (unburned hydrocarbons, CO2 (good fuel efficiency), CO, etc.

they figured back then that if the car could get 4.7l/100km around town and 5.5l/100km on the hiway, it was automotically good for the environment....i would generally agree.

the biggie is injection timing - advanced injection created very intense peaks in cylinder presure and this is when the NOx is produced. on pump diesel, you can combat this by running injection timing a little retarded but at the expense of allowing other emissions to increase a little. on ester based fuels (Bio D) the higher oxygen content of the fuel allows for retarded injection timing without worsening other emissions in some cases - so depending on hte study you read, you might be able to decrease the nitrous emissions by running bio-diesel and retarded timing.

multi-stage injection goes a way towards improving this i believe, but with direct injection diesels there is no mechanical barrier to prevent the high peak cylinder pressures apart from the multi stage injection or running poor combustion (EGR). the old indirect injection prechamber diesels allow for a smoother more controlled flame fornt propagation, since the diesel is injected and combusts over a long period of time with respect to piston travel and must expand out into the cylinder through the pre-chamber port. not ideal for making big torque (all the IDI's make less torque at low rpm compared with the TDI's) but better for emissions in this case.

this site has some text extracts on the subject:

http://www.journeytoforever.org/biodiesel_nox.html

[tonymaroney]

Intake pipe

Greg you mentioned that you might look into the EGR system over xmas...are you going to pull off the intake manifold? (in my diagram they call it the intake pipe...number 5 on your picture). I am just wondering if it would be possible to unbolt the intake manifold, egr intake pipe etc and the big rubber air feed pipe at the bottom and lift the whole manifold+egr valve+flap motor out in one go? The gasket for the intake manifold looks expensive! Where do you get your gaskets and O-rings from in Brisbane?
Also I am looking at one day getting a Vagcom-USB cable etc...if you have one where did you get yours and how much did it cost?

I have come to the distinct conclusion that I have babied my motor too much and inadvertently may have gummed it up...first stage I think will be to just clean it all up as best as possible, then I'll stick to good fuel. A Provent might be on the cards if I go to all the effort of cleaning the system up. And I might consider a Bluefin ecu flash too (for fun!), but those EGT temps are a worry. Electronic EGT monitoring doesn't look as easy/cheap as I'd hoped so I'm not so sure I can do that...I might just have to be mindful of the EGT temp and not go too crazy for too long a period!
Thanks again for the helpful posts above!
Tony

[Greg Roles]

Tony,

No way I'd pull the manifold, purely for the hassle of the gasket, and mine is virtually clean, and staying that way! You'd get the gasket from any VW dealer such as Austral, but it would still be a mission to replace.

I'll photograph the EGR thing and add it to my thread, don't worry!

Vag Com comes from ross-tech, simply no better option at the moment. The software is free to download, you pay for the cable.

A standard reflash such as Bluefin would be fine EGT wise, they allow for that. I'm aiming for a custom, max effort tune.

A scan guage 2 costs a few hundred, but simply plugs in to your CAN port under the dash, and you get all the readings you could ever want, too easy!

Take your car for a good drive up the coast sometime, this supposedly cleans out a fair bit of sludge, sustained higher speed driving. You'd have to have done 100k plus to be in potential problematic sludge territory from what I undersand of it all. Just pop off the lower rubber inlet hose and you have access to the throttle flap and the EGR valve, you can clean them out a bit from underneath. Don't go nuts with spray cleaners, lest you fill the manifold and have a max rev on next start! Little spray, let it drip back out, repeat!

[tonymaroney]

Italian tune up

I did an Italian tune up the other day and think it helped with the level of particulates I see out the back. My car doesn't have a DPF and I get a lot of brown particulates out the back normally (and while I feel this could be related to the EGR valve, I also could be overfueling, which probably is more to do with the MAF sensor or maybe even the ECU getting a bit out of wack).

So you feel that your manifold is clean because of the Provent? I haven't got a provent so I would have thought I would have gunk all the way through that system.
I saw the Rosstech cable...does it matter whether you use the expensive Ross-tech cable or the cheaper ones on the net?

I'll have a look at cleaning the system as best as possible without removing it, and have heeded the warning about the spray cleaners! I saw earlier on in this thread or another one that someone used diesel as the cleaning agent, thus reducing max reving at next startup.
Tony

[Greg Roles]

Hey Tone,

I've got the cheapest Micro Ross-Tech cable, but I'm unsure how well the cheapie e-bay type work, perhaps start a thread in the MKV section?

Anything that impedes the air /diesel ratio ( ie overfueling like you mention 0 will give a lot of soot. Dirty air cleaner, dirty MAF, dirty injectors ( usually ), so perhaps putting some "Fuel Doctor" or similar from Supacheap through it would be a good idea. I do that every several thou, and only use BP ultimate.

You're welcome to drop round and borrow my Vag cable mate, it's not being used at the moment.

How many kms has your car done? Higer kms equals higher chance of gunk. I put my Provent on virtually from new, so I've managed to stop it pretty much from happening at all.

A diesel wil run on metho, carbie cleaner, oil, veggie oil, almost anything really, so it doesn't matter what you put in the inlet, if it can end up in the cylinders, well it's gonna rev! I used full on carbie cleaner, as I figured being more volatile, it would be the quickest to evaporate off. One of the commercial cleaning systems I saw on here ( somewhere ) had you putting a restriction plate over your air inlet, basically limiting the amount of air that can flow, and had you spraying cleaner down the inlet with the car running. The small hole in the restriction plate kept the car revs down, which was a great idea! Perhaps something worth doing, a restriction plate would be a lot easier to rig up that pulling manifolds off!

[CatonaPC©]

There's certainly going to be a lot of TDI's having problems from sludge over coming years as they rack up the miles.

And I am led to believe by all this discussion that VW don't have some set service interval procedure to take care of this for those of us who do not wish to tamper with their TDIs in any way?

For those who want to tinker, this discussion is quite interesting and mostly informative, but for those who do not and just want to maintain our car's reliability (and above all, originality), what course of action is open to us?

I find it difficult to believe that VW aren't aware of the issue and don't have methods in place to manage it for the majority of TDI drivers out there.

[Greg Roles]

....what course of action is open to us?

Extended warranty for when it finally stops is about it.

[Preen59]

I find it difficult to believe that VW aren't aware of the issue and don't have methods in place to manage it for the majority of TDI drivers out there.

Unfortunately they seem to have turned a blind eye to it.

This is something i must do for the Caddy. I'm considering the Moroso total loss system aswell.. That seems like a good idea. To be perfectly honest (and i really don't care how anyone else feels about this..) i'm not worried if it increases the pollutants in my exhaust gasses if it increases the reliability of my vehicle. Considering the fact that i'm doing everyone else a favor by not driving a carbied petrol engine around every day anyways.

I also think global warming as a crock of **** but this isn't the thread for that discussion..

Greg, have you done anything with the Moroso kit? What is involved in doing it and does it affect any part of the ECU, by means of upsetting the tune etc?

[Greg Roles]

Moroso has been in and running fine for several weeks now, it enters after the last sensor for the DPF, but on the caddy you'll be able to get it up higher as you don't have as many sensors to worry about. Higher equals hotter equals more oil vapours burnt. If it doesn't enter before a sensor, then there's no way it can upset the ECU. The ECU / lambda probe is only measuring EGR anyway, no way it measures the amount of oil vapour. I'm hoping my forthcoming CC tune can edit the EGR sensors out, as that's getting hobbled as well. When the car is driving and I'm getting exhaust temps of a few hundred degrees I figure it's burning off pretty well, only seems to be an obvious problem on idle, but only from a bit of an oil fume smell, absolutely no different to anyone else running a total loss to atmosphere catchcan. Nowhere near as bad as the times I've tried running a gas engine with total loss crankcase venting, that much oil smell does make you a bit sick, and I've never perservered with it till the TDI.



When the new DPF less dump pipe arrives, I'll be talking to JBS and CC to work out just how high I can put the moroso, given a lot of the sensors will then become defunct. It's definately going back in, but as high as possible.

[CatonaPC©]

Extended warranty for when it finally stops is about it.

I bet the fine print won't.

Unfortunately they seem to have turned a blind eye to it.

Well, I'd be interested to hear from someone who works at a VW dealership service department for any comments they may have.

I also think global warming as a crock of **** but this isn't the thread for that discussion..

No it's not. It's real. What IS a crock of **** is the assumption that we can actually do something to reverse it.

[tonymaroney]

Hey Tone,

I've got the cheapest Micro Ross-Tech cable, but I'm unsure how well the cheapie e-bay type work, perhaps start a thread in the MKV section?

Anything that impedes the air /diesel ratio ( ie overfueling like you mention 0 will give a lot of soot. Dirty air cleaner, dirty MAF, dirty injectors ( usually ), so perhaps putting some "Fuel Doctor" or similar from Supacheap through it would be a good idea. I do that every several thou, and only use BP ultimate.

You're welcome to drop round and borrow my Vag cable mate, it's not being used at the moment.

How many kms has your car done? Higer kms equals higher chance of gunk. I put my Provent on virtually from new, so I've managed to stop it pretty much from happening at all.

A diesel wil run on metho, carbie cleaner, oil, veggie oil, almost anything really, so it doesn't matter what you put in the inlet, if it can end up in the cylinders, well it's gonna rev! I used full on carbie cleaner, as I figured being more volatile, it would be the quickest to evaporate off. One of the commercial cleaning systems I saw on here ( somewhere ) had you putting a restriction plate over your air inlet, basically limiting the amount of air that can flow, and had you spraying cleaner down the inlet with the car running. The small hole in the restriction plate kept the car revs down, which was a great idea! Perhaps something worth doing, a restriction plate would be a lot easier to rig up that pulling manifolds off!

Greg...Car has done 60K now, and I'm really regretting not knowing about the ProVent until now!
Thanks for the offer of the cable...I might take you up on it, but I'm also keen to get one myself! I'm sure my other 3 VW-owner mates won't mind too much.
More questions!!!....
1)With the Provent (before it was plumbed to your exhaust) did you just close off the bottom drain valve and drain it out every couple of thousand klms? I assume the Provent can hold a few hundred mls of oil inside it and still work ok? (The brochure just assumes you will have it draining back to the sump all the time, with no oil collecting in the ProVent).
2) Apart from the EGT increase that we discussed earlier, if you did want to reduce/stop the EGR but not install a straight-through Powerpipe etc, what are the other disadvantages of using Vagcom to reduce the EGR down to virtually nothing: http://www.tdiclub.com/TDIFAQ/TDiFAQ-7.html#j If you did use VagCom to reduce the EGR, would the oxygen sensor downstream still freak out, or would it "know" to expect more O2 coming it's way?

I assume that if a Provent is installed then I suppose there is no need to block down the EGR, because you have all the "benefits" of EGR and much less of the gunk problem.
Tony

[HiTorque]

I just found a reference to this kit, pls comment, it isn't too expensive..

http://www.egrvalve.co.uk/index.php?page=home