3.0tdi intake removal and clean..

Gmac

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Looking at getting my 3.0tdi manual remapped. But first I think I should remove and de-coke intakes/y-pipe and throttle body. Is this a fairly straight forward job? Ive watched a video on the a6 engine, think it’s the same? Any top tips.. thanks mine is the bkn engine If that makes any difference?
 
I did mine when I changed the manifolds.
I had remap & EGR delete, and blanked the EGR port.
The turbo duct was clean & shiny up to where the EGR T's in, from there on it was all thick tar.
The duct work I did in caustic soda, the replacement manifolds were clean anyway but the 24 valve ports were painful, diesel, rag, stiff artists brushes, airline & patience.
If you've got fat fingers you'll struggle.
BUT, unless you're blanking the EGR, I wouldn't bother it will tar up again in no time.
Hope that helps.
 
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Thanks bud, yeh, all useful. I’m guessing its fairly straight forward getting the bits off the car? Sounds like blanking the egr is the way forward, and I’m sure @Rick @ Unicorn Motor Dev. would map it out.
 
Thanks bud, yeh, all useful. I’m guessing its fairly straight forward getting the bits off the car? Sounds like blanking the egr is the way forward, and I’m sure @Rick @ Unicorn Motor Dev. would map it out.
you dont need to map the egr out, is not clever enough to work out you have blanked it, i just got a ali blanker off ebay and fitted it ar the inlet side dead easy job, did this literally as first job when i got the car a few years ago, since doing this im sure the whole inlet is cleaner and the oil in-between changes is also definitely cleaner.

You have to be careful with maps on the manual as the dmf is fairly poor, even with a brand new dmf and clutch its extremely easy to get judder from torque loads at low rpm, you can map them hard if you drive them 'like a petrol' but if not heavy loads at low rpm are just too much.

i got a kess off ebay and have messed around with loads of maps on my car in my experience you wont get loads extra before the judder, but see how you go, mine was rr tested too sweet spot around 260 i would imagine, but still if you happen to catch it at really low revs in a high gear it will judder.

cleaning the inlet is a nightmare i got some inlet cleaner from ecp that melted paint! was bl0ody good though!
 
Forgot to mention the egr is vacuum controlled so you dont even have to blank it, you can simply pull the vacuum hose off the valve that controls the egr flap
 
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@Sloppy_1

I would be very surprised if the 3.0 TDI didn't throw any sort of error if you blank off the EGR, without any change to the ECU software. I know for certain on both the 140 and 170 2.0 PD TDI, if you blank the EGR without software changes, you will get a check engine light on the 140 (it did on mine before I updated the ECU software to map it out), inconsistent power delivery, and full limp mode on the 170 as the EGR is required for DPF regeneration (which the 140 does not have, this is why it doesn't go into limp mode). Now my knowledge on the 3.0 TDI is not as good, but from what I recall only the 2005 (possibly some early 2006) models came without a DPF. In which case, I expect you would see the same behaviours mentioned above on a stock vehicle, depending on the equipment fitted.

With respect to the ECU being dumb, you are incorrect, the Bosch EDC16 ECU fitted to our cars is definitely clever enough to know when the EGR is not working. Even the earlier EDC15 ECUs were smart enough to figure that out. The ECU contains a mapping table in the EEPROM that has the expected MAF values for all given RPMs and loads. There will also be another table that contains the requested values for exhaust gas recirculation under those conditions. Let's say 500mg/sec of air is coming in via the inlet manifold, and the ECU has been mapped to recirculate 200mg/sec of exhaust gas for the current RPM and load. The ECU will adjust the EGR electrovalve duty cycle (and on some diesel cars, close the EGR throttle / anti-stall valve to assist this) until it sees only 300mg/sec of fresh air passing the MAF. At that point, it knows 200mg/sec is coming in via the EGR system, and the target has been met. If it cannot achieve the requested value, then it will throw a code (EGR valve efficiency not met, or something similar), and give a check engine light at minimum.

For reference, another thread here where a forum member had this code thrown on their 3.0 TDI:


Code:
4807 - EGR System: Insufficient Flow
 
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Thanks for all the bits of info folks. The dmf and clutch was something I haven’t found much info on as to whether it can take a map or not. But figured a stage 1 would be fine. @Sloppy_01, night mare as in a lot to clean and is a dirty job? Having a look at the mechanics side of things it doesn’t look to bad from what i’ve seen.
 
@Sloppy_1

I would be very surprised if the 3.0 TDI didn't throw any sort of error if you blank off the EGR, without any change to the ECU software. I know for certain on both the 140 and 170 2.0 PD TDI, if you blank the EGR without software changes, you will get a check engine light on the 140 (it did on mine before I updated the ECU software to map it out), inconsistent power delivery, and full limp mode on the 170 as the EGR is required for DPF regeneration (which the 140 does not have, this is why it doesn't go into limp mode). Now my knowledge on the 3.0 TDI is not as good, but from what I recall only the 2005 (possibly some early 2006) models came without a DPF. In which case, I expect you would see the same behaviours mentioned above on a stock vehicle, depending on the equipment fitted.

With respect to the ECU being dumb, you are incorrect, the Bosch EDC16 ECU fitted to our cars is definitely clever enough to know when the EGR is not working. Even the earlier EDC15 ECUs were smart enough to figure that out. The ECU contains a mapping table in the EEPROM that has the expected MAF values for all given RPMs and loads. There will also be another table that contains the requested values for exhaust gas recirculation under those conditions. Let's say 500mg/sec of air is coming in via the inlet manifold, and the ECU has been mapped to recirculate 200mg/sec of exhaust gas for the current RPM and load. The ECU will adjust the EGR electrovalve duty cycle (and on some diesel cars, close the EGR throttle / anti-stall valve to assist this) until it sees only 300mg/sec of fresh air passing the MAF. At that point, it knows 200mg/sec is coming in via the EGR system, and the target has been met. If it cannot achieve the requested value, then it will throw a code (EGR valve efficiency not met, or something similar), and give a check engine light at minimum.

For reference, another thread here where a forum member had this code thrown on their 3.0 TDI:


Code:
4807 - EGR System: Insufficient Flow

Mine threw up an eml about 2 hrs after egr blank
2007 without dpf fyi


Sent from my iPhone using Tapatalk
 
I blanked mine on both hot and cold side before taking it for remap and tune at the tuners request.Not 100% sure why ,maybe something to do with flow and back pressure from turbo
Happy I did as removing the egr and pipe work has made access around the engine and lot easier and also tidied up under the engine cover


Sent from my iPhone using Tapatalk
 
@NM07 be very supprised!!

Mines a dec 2006 no dpf, (amazingly after researching dpf fitment on 3.0 you can get 2007 models with no dpf) hence no code, I assure you all I did was remove pipe then drop in blanker at a later date, just pull vacume pipe you will soon know
It will give you a code if you unplug the vacuum solenoid so just remove pipe.

strangle my modeo st tdci of same vintage does detect it, the ecu looks for some flow change in th egr pipe so can tell it’s blanked but only puts up engine light no other issues. Think it’s the difference between euro 3 and 4 as I think early modeos could be blanked no code.

the egr is vacuum control on these engines not electronic like the capa engine so it can’t tweak the rate it’s giving it’s either on or off, the guy you linked in your post had the later engine hence his code prob in b8

The inlet is actually easy to remove its just awful stuff to clean it’s very tough.
 
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You have to be careful with maps on the manual as the dmf is fairly poor, even with a brand new dmf and clutch its extremely easy to get judder from torque loads at low rpm, you can map them hard if you drive them 'like a petrol' but if not heavy loads at low rpm are just too much.
This is my reservation about power mapping any of these cars, for anything other than economy and a mild bit of extra low torque. If I had a 3.0TDI as opposed to my 2.0TDI I would be even more reluctant since it's a strong fine motor anyway. I think personally they should never be ragged like a petrol, it should not be necessary with diesels. A quick assertive blip to just over 2K is what I always use, rather than a slow acceleration build up. It sounds smoother that way too, less of a tractor and I'm sure it keeps it cleaner. These engines were mapped from stock very conservatively and often appear to have less low down torque than you would expect from a diesel; mainly because of environmental reasons and longevity of the not so tough turbos, clutch and DMFs. Nonetheless a bit of extra torque should not be the end of the world as long as they are not ragged, like a petrol. Inadequate low end torque in too high a gear can be just as damaging on the clutch/dmf too.
 
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This is my reservation about power mapping any of these cars, for anything other than economy and a mild bit of extra low torque. If I had a 3.0TDI as opposed to my 2.0TDI I would be even more reluctant since it's a strong fine motor anyway. I think personally they should never be ragged like a petrol, it should not be necessary with diesels. A quick assertive blip to just over 2K is what I always use, rather than a slow acceleration build up. It sounds smoother that way too, less of a tractor and I'm sure it keeps it cleaner. These engines were mapped from stock very conservatively and often appear to have less low down torque than you would expect from a diesel; mainly because of environmental reasons and longevity of the not so tough turbos, clutch and DMFs. Nonetheless a bit of extra torque should not be the end of the world as long as they are not ragged, like a petrol. Inadequate low end torque in too high a gear can be just as damaging on the clutch/dmf too.

This is quite a common misconception people have about diesel engines, and even just engines in general. Just because diesel engines produce a lot of torque (and therefore power) lower down in the rev range where they are at their most efficient, does not make it mechanically easier for the components to deal with. A lot of people see power and torque as two separate measuring values, and while that's true to a degree, you must remember that torque is an instantaneous value, whereas power is a function of torque, over a given unit of time (also known as work).

An example tends to make this easer to visualise. Both of these engines are doing the same amount of work:

Power = Torque * RPM / 5,252

Diesel engine - 200lb/ft @ 2,000rpm -> 88hp
Petrol engine - 100lb/ft @ 4,000rpm -> 88hp

Now in the above example, for each power stroke, the diesel engines connecting rod has to be pushed twice as hard, in order to make up for the fact it is spinning at half the rate. This means considerable extra stress on components that are feeling these larger surges per stroke, which is why diesel engines have stronger rods, cranks, and main bearings than their petrol counterparts, as well as components like dual mass flywheels, which (aside from smoothing the delivery) protect the gearbox input shafts from breaking due to mechanical fatigue. You will find threads dotted about on various forums where people have done single mass flywheel conversions on their mapped diesels and destroyed the gearbox because of this.

When you mention about being ragged like a petrol, up to a point, it is actually easier on a diesel engine when driven hard to be at higher RPMs, due to the factors I mention above. A diesel engine will be producing a lot less torque above 3,000rpm than at 2,000rpm, but the fact it's rotating 50% quicker makes up for that deficit, and still results in a higher overall power output. A case in point is this dyno graph for a stage 1 BKD 140 (essentially a transverse mounted BRE, like we have) from Darkside:

1672780167603


Remembering that torque is an instantaneous measure of twisting force, we can see from this graph that the engine is under the most mechanical stress at a touch over 2,000rpm, at peak torque, when cylinder pressure is at it's highest. Considerably less stress is being put through the components at 4,000rpm as torque output is lower, but as it's rotation faster, is still still making more power (doing more work). Anything above that, and we will start to see that due to the heavy rotating components of a diesel engine, coupled with the small turbine on our BRE engines that cannot keep producing target boost at high RPM without over-speeding, mean it falls out of it's efficiency zone and power starts to drop for engine safety.

Now there is an upper limit here where the increased rotational mass of the heavier internal components of a diesel engine starts to brings it's own stresses, but any of the more modern diesels in our B7 will happily accept being revved out to 4k rpm in each gear with no mechanical concerns. Certainly that will be far more forgiving and less wearing on the components than full throttle labouring from 1,400rpm - 2,200rpm which is what a lot of drivers do with their diesel engines as it's what feels most natural (surfing the wave of torque). You will find that style of driving is what is hardest on all engine and drivetrain components.

This is why @Sloppy_1 said you can map 3.0 TDI engines hard if you drive them like a petrol, as at high RPMs the internal components of the 3.0 TDI will be under much less stress, as the torque produced at the high end of the RPM range is far more manageable, and combined with the higher RPM means for a high power output.

I realise I've just written a large wall of text, I love mechanical engineering, apologies for getting carried away :sweatsmile:
 
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This is my reservation about power mapping any of these cars, for anything other than economy and a mild bit of extra low torque. If I had a 3.0TDI as opposed to my 2.0TDI I would be even more reluctant since it's a strong fine motor anyway. I think personally they should never be ragged like a petrol, it should not be necessary with diesels. A quick assertive blip to just over 2K is what I always use, rather than a slow acceleration build up. It sounds smoother that way too, less of a tractor and I'm sure it keeps it cleaner. These engines were mapped from stock very conservatively and often appear to have less low down torque than you would expect from a diesel; mainly because of environmental reasons and longevity of the not so tough turbos, clutch and DMFs. Nonetheless a bit of extra torque should not be the end of the world as long as they are not ragged, like a petrol. Inadequate low end torque in too high a gear can be just as damaging on the clutch/dmf too.
you dont have to rag it as such but with a map it delivers such a massive amount of torque at low revs in certain circumstances it overloads the dmf,

if you are crusing along at say 40 go up a gear and then floor it say the revs are at 1k and you literally foot to the floor as the turbo is big there is alot of lag, it slowly accelerates then as the boost kicks in at say 1800 rpm there will be a massive surge of torque which overloads the dmf.

when i say drive like a petol in the instance you would drop a gear, and likely should in a derv! , if you just accelerate normally through the gears with sensible momentum you will not notice it, its literally when you catch it at low revs under load as the turbo kicks in.

depends how much power you want i suppose, for me its a cheap fun car i paid just over 2k for so i dont really have much mercy.

@Gmac its a shame your not more local as i would show you exactly what it does, and show you how to remove inlet!
 
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When you mention about being ragged like a petrol, up to a point, it is actually easier on a diesel engine when driven hard to be at higher RPMs, due to the factors I mention above. A diesel engine will be producing a lot less torque above 3,000rpm than at 2,000rpm, but the fact it's rotating 50% quicker makes up for that deficit, and still results in a higher overall power output. A case in point is this dyno graph for a stage 1 BKD 140 (essentially a transverse mounted BRE, like we have) from Darkside:
I'm afraid I don't agree. The 140 particularly has both it's power and torque band best from 1750-2500 rpm. Modern diesels like this are very narrow in that respect. Revving to over 3000rpm to change gear is totally unnecessary and wasteful. But hey if you like to push it hard as Sloppy does, I'm no killjoy. :) I've always liked to drive smooth, just me, having driven professionally, including a stint as chauffer. Ever since I adopted the quick firm blip to just over 2K, until the kick of the turbo takes hold decidedly, my engine has stayed a lot cleaner and smoother than before, infact I would say it's rarely if ever been above 3000rpm (except for the blinking MOT) for anything, since 2200rpm is about 80mph in 6th anyway, but as they always say YMMV ;)