Downgrading the Audi Alls*hit

Downgrading the Audi Allroad 2.5TDI(AKE) to 1.9TDI(AVF)

Hi guys, first of all i want to thank everyone that keeps this forum alive, and shares it´s knowledge for free, it´s been extremely usefull, you guys are awesome.
Now, long story short, i´m fed up of the AKE V6 TDI on my recently acquired allroad, and allready bought a B6 A4 "halfcut" AVF 1.9 TDI to "downgrade" my allroad(eventually will be upgraded to 200bhp+)
I´ve seen a few 2.7t gas converted ones, but no single 2.5tdi one around here or anywhere, but i know it´s been done several times, but no real info around, i assume it´s easier(??)
Anyway right know i do not have many questions but pretty sure will have as soon as i start the conversion. As many of you i´ll be a good guy and share my knowledge and for sure troubles and hickups.
My 2 baby´s, the A6 is also mine:
https://1drv.ms/u/s!AlY1eE2P7cvOphumzPGmPRqTMbPj
Donor:
https://1drv.ms/u/s!AlY1eE2P7cvOphrtEcc0UlRXjXtI

Both look very nice.

What have the problems been with the V6 TDI that make you want to remove it? Cams and IP or other issues?

I have a 2001 Allroad 6spd that I am gathering parts for a US 2.0 PD swap in, but would much rather use the V6 TDI if I could get one.

Any interest in selling the complete V6 TDI setup after you take it out of yours?

I bought it cheap(ish), with an unkown problem, hard to start. After alot of diggin i discovered it was the fuel cooler, coolant in the fuel system, solved that, car run fine for 2 weeks, then started to have hard starts again. So after much diggin again i discovered it was air in the fuel system, replaced some hoses, some non retun valves problem solved...
Then again run fine for a week or so and started to do the same, air in the fuel filter, it appears the IP is gone, "scratched" inside??? or lets air in somwhere??, and since the fuel filter is above it, the air rises from IP to filter... i´ve seen it.

I could repair it, or give it more of my time, but i really don´t like this engine, i wont bother, the turbo is laggy, the torque curve is narrow, it´s not good on fuel, not really that fast, aparently it has all kinds of other problems like the cams, and such associated with it despite this particular engine seems healthy... overall it´s slow in stock form. The only plus is the sound and the smoothness.

It´s just my opinion, it´s worth what it´s worth, some friends love it and call me insane, but i want to go trough with it.

Yes i would sell the complete swap, engine, ECU, wiring, etc etc, but i never sent anything this big or heavy overseas.

Hi guys, i´m starting to rebuilt the AVF, and looking more indepth into the swap... especially the electronics, harnesses etc

So both A4 b6 and and A6 c5 have can-bus communication... A4 uses EDC15p+ A6 uses EDC15VM+ ECU, the plugs are the same... i´m planning using the A4 AVF engine harness and EDC15p+ ecu and mate it with the allroad chassis/cabin harness near the "electrical plenum(?)", but there´s 1 extra orange connector plug on the allroad, that´s not present on the AVF harness.



Anyone know what it is? Maybe it´s related with the optional "low range" manual gearbox?

I have the complete interior A4 B6 harness, cluster and key, but gonna remove the IMMO 3, since the a4´s cluster is diferent in form and shape from the A6´s, then i realized there´s AWX/AVF´s A6 were i live, maybe i can get a 1.9 cluster and use that with the chassis A4 harness but that would be dash out job, on the plus side would avoid to repin, or cut any wires to the cluster, this if all other plugs and ecus in the allroad are a direct fit to a4 harness, wich i doubt.

Allroads and A6´s(AVF/AWX), A4´s B6 use 2 common 32 pins, the green and blue, but differ on a 3rd plug.



So resuming, Cluster´s are different and engine to chassis harnesses is missing a orange connector on the AVF engine side.

So im trying to define a strategy to adress the issue and this crazy noob idea came to mind, can i simply wire the 4 plugs from the AVF to the allroad chassis side and see what it does?? or i´m risking frying the ECU, cluster, etc etc What did the 2.7t to BGW guys did? "Repin" first?

EDIT: Nevermind all the above, it´s been a steep learning curve, and i´ve been studying quite hard... so just ignore the post, the plugs don´t even match and i found my strategy.

Updating: Long story short, the manual gearbox(kinda) broke so i demoralized a bit... this and the AVF i bought was a bit of a lemon...

So bought a long ratio (A6 quattro) DQT gearbox and diff(4.11) and decided to rebuild the AVF head... just to find the cam was ruined, the Hydraulic lifter had a hole, and the head was cracked and full of EGR gunk...

Aparently its pretty common, it was almost unanimous that every PD is cracked, and alot of people run them like that, with no ill effect, a guy even told me is nitrous 300+ ibiza run fine with the cracks... it´s only worrying when it reaches the injector seat... ***! Did anyone assembled the head like that?

Some Pics and more news soon

I swapped a BHW and DQT into a 2001 AllRoad. Pretty straight forward. Used a cluster for a A6 TDI.

The euro version of the BHW is a BGW. The orange plug has

fuel pump relay 85, blue/red

ignition srarter switch d/15 black

cruise/brake/clutch red/white

fuse 18 feeding ecu, n75, pcv, motor intake flap red/green

vwztips said:

I swapped a BHW and DQT into a 2001 AllRoad. Pretty straight forward. Used a cluster for a A6 TDI.

The euro version of the BHW is a BGW. The orange plug has

fuel pump relay 85, blue/red

ignition srarter switch d/15 black

cruise/brake/clutch red/white

fuse 18 feeding ecu, n75, pcv, motor intake flap red/green

Click to expand...

Thanks for your reply... The BGW is as i understand a stroked AVF/AWX with more emissions stuff basicaly... so i thing the AVF should be about the same hardware wise... The plugs im not that far yet... but i have a passat b5.5 AVF ECU and harness for the B6 AVF engine... expect it to make it easier.

What diff did you use with the DQT? The allroads have the short 4.3 ratio, the DQT is 4.11, so i bought a CUB diff, wich matches, but i found another problem, my Allroad as a "low range" gearbox, and it´s about 20cm longer than the DQT, so i need a new a longer driveshaft.

Does a normal A6 quattro driveshaft fit the allroad? lenght wise i mean... i know the central bearing is diferent, because of the height in the suspension and subframes...

The A6 2.7t had 4.11 rear diffs. I used it and the prop shaft from a 2000 A6.

As regards to the cylinder head cracks by the injector holes, I too have seen several heads like this and it has no ill effects on re-using the head, Also on high powered PD's 300+ hp without nitrous and daily drivers

vwztips said:

The A6 2.7t had 4.11 rear diffs. I used it and the prop shaft from a 2000 A6.

Click to expand...

Ok, they fit, anyone know if the Auto, being tiptronic or not, and or manual have the same lenght?

The reason i ask is i can get plenty of auto propshafts, manuals are quite rare... i can confirm that manual with "low range" are 20cm shorter then normal a6 quattro 6 speed.

CasaEd said:

As regards to the cylinder head cracks by the injector holes, I too have seen several heads like this and it has no ill effects on re-using the head, Also on high powered PD's 300+ hp without nitrous and daily drivers

Click to expand...

Yea, i´ve read alot, and talked about this with some well informed people, all said the same... but me being a perfeccionist, i don´t like that at all... and im after 200bhp/400nm on a 2ton AWD "house", so it will be properly stressed engine.

It´s in... now comes the hard part... figuring out the tubing and electrics... im not using the passat front end. Because i don´t have it and because i want the big FMIC.

I´ll let you know how it´s coming along...

Hi guys. already made some stuff work pretty easy, but run into a major issue... not new for some of you guys...

The AC compressor in the C5 is a "clutch type", and the a4 b6 is variable displacement... and it´s controled by climatronic unit E87, using what it seems to me a PWM signal...

Page 59 and 60: http://pierro777.free.fr/DOCVAG/ssp240_Audi A2 Technology.pdf

The signal: https://workshop-manuals.com/audi/a...conditioner_compressor_regulating_valve_n280/

Did anyone managed to use a clutchless compressor on a clutch type system... using the one wire to turn on or off the compressor? Did anyone manage to "simulate" a signal to the compressor, like fooling it to work at 80/100% duty cycle? Maybe this is a noob question

If i cant find a way, ill ditch the a4 b6 compressor and use a b5.5 passat compressor and support on the turbo side of the engine, but the damn snub mount is on the way, and the oil pan is diferent... Don´t know if the support will go with this oil pan, the snub mount is easily removable, and can and will fabricate a gearbox suport as B6´s have... this quattro gearbox are really bad suported. Aparently all newer chassis have a 3rd GB mount.


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Nevermind the previous, already sorted the physical part of the swap(almost)...

Didn´t start the car yet, since i´m missing the fuel lines and pump, but plugged the battery just to see what´s up... got 5 errors, wich only 1 worrys me... quite alot:

18020/P1612- http://wiki.ross-tech.com/wiki/index.php/18020/P1612/005650
18048/P1640- http://wiki.ross-tech.com/wiki/index.php/18048/P1640/005696
18044/P1636- http://wiki.ross-tech.com/wiki/index.php/18044/P1636/005686

The 18020 and 18044 seem to be code related, and unit mismatch, etc, but i still have some stuff disconnected and not paired yet...

But the 18048 seems ECU/chip related and hard to solve, really don´t know how to deal with that. The ecu is a standard PD130 passat with immobilizer delete and soft tune for stock injectors and turbo, from a reputable chiptuner.


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Any toughts on this particular error?

Hello, did you complete your allroad engine swap?