I equally love and hate German engineering
Hello everyone.

So last week I've bought a used a4 b8 3.0 tdi (240hp) manual quattro. It's a 2008 model with 230000km on the clock. The hood and front mask have a few stone chips but nothing major and not very noticeable. The chassis is from S line so its 3cm lower from the factory. It also came with 19" rims that are usually mounted on RS. The second set of rims (17") are for winter. The interior is very well preserved and looks like new. On the test ride no issues are immediately noticed. As I dig deeper into the car inspection the engine warning light came on. The seller called a friend to hook it up and check what the error is about. It turned out to be and idle sensor on the fuel pump. The cable itself was visibly damaged and was literally held by two threads. He then said that some time ago mice came in the engine bay and ate two cables that they later repaired. One of repaired cables was the one that was now causing problems. I also noticed the battery was a bit weak. After a while we agreed on a price and I drove off. Car runs smooth and ride is comfortable. On the way home I've noticed that the engine temp never got past 80°C. That's something I didn't notice before since it didn't had time to warm up.

Fast forward to next day.
After going back from work the DPF filter error pops up. So after coming home we hooked it up to friends pc and noticed that there are quite a few errors that need addressing. The most important ones:
00256 a/c - upon pressing the ac button the red light is lit only while the button is pressed. I yet have to check the sensor and if there is any pressure in system.
00457 Control Module for Network (J519): No Signal/Communication - no solution for this one atm
P063800 throttle body - This was clogged up and some teeth at WOT position were nearly non existing so I've replaced this. The most likely reason for this IMO is that the thermostat hasn't been working for a while so the economy was rubbish which clogged up a lot of stuff and now it needs a thorough cleaning. Also the default position for throttle body is open. Which means when the residue solidified it had to move from that position. Now the worn out teeth make sense. Pic below.



So after replacing throttle body we went to another friend to perform the regeneration. Car at this point has flashing glow plugs and in in limp mode. The attempt to perform regeneration was unsuccessful and it constantly got aborted for "safety reasons". We're aware of non functioning thermostat and the replacement has been ordered. However further investigation showed up another error that no description. U1008 00 [039]
I've found some info that points toward transmission? No further clues at this point. So the regeneration failed and I limped back home. We'll either do the regeneration somehow or start gutting it. If anyone has any info that could be useful ... I also wonder how much HP can stock clutch handle since I plan to chip tune it?

On the long run I plan to ditch the egr, dpf and clear the muffler for better flow.


I equally love and hate German engineering
We managed to trigger the regeneration. After a handful of different programs autocom finally managed to trigger the process. The calculated soot was 36g. Next on the list is a thermostat replacement.


I equally love and hate German engineering
~900km later the particulate filter error poped up again and this time around I won't bother with regeneration. I'll clean it permanently and get rid of the problem that is causing this in the first place. So things go like this in the meantime I've ordered a replacement gears for original throttle body. The aftermarket TB is constantly throwing up an error ever since it was installed even though the car drives fine. Original TB looks like this with its worn cog.



The intake manifold is full of black sticky stuff. I can only imagine how the dpf looks like. BTW the car doesen't feel like 240hp. More like weak 200. My old B6 chipped to 160hp is more lively than this V6.

Also installed a dipstick since the car says there is no info on oil level most of the time.

Next on the list in intake cleaning swirl flaps removal, dpf and egr delete.


I equally love and hate German engineering
I've been busy. Removed exhaust and cut one side open. Removed the internals but it isn't finished yet so more about that in the future. The sound with no rear part of exhaust is pathetic. I mean its literally no difference compared to complete exhaust system and the reason for this is clogged dpf.



Clogged dpf. View from exhaust side.

View from turbine side

Time to cut it open. I've cut it on the weld where is thickest so welding it back should be easy since there is enough material. All of this is also on the back and not visible when installed.





Some of the modification enthusiasts. After I've removed the big filter I also chiselled out the small one. I made a chisel from a rebar so it was long enough and worked it out.

And a view of the engine bay with no dpf and firewall.

More follows.


Drive It Like You Stole It
That pic of Greta :)


I equally love and hate German engineering
Re welded the DPF

carbon buildup



Pro tip if you tend to forget which bolt goes where.


I equally love and hate German engineering
Fixed the original TB and put it back in place. The aftermarked cogs didn't fit perfectly and TB got stuck in certain positions so I trimmed it a bit so it moves smoothly.



I equally love and hate German engineering
What a PITA. Getting those swirl flaps removed is truly a job for someone with patience. I've tried to remove as little hoses as possible and gotta say it proved to be quite difficult but in the end we managed to do it. Left side is already replaced and back in place while right one is siting on a workbench waiting to get cleaned. To my surprise the flaps were moving smoothly and there wasn't a loot of accumulated soot. While cleaning I've noticed is that both manifolds have dates from end of 2012. Which is quite interesting since the car itself is from 2008. Maybe they were replaced even though there was no visible damage on bolts, cabling, pipes etc. or maybe the whole engine was replaced? idk. We'll see.


Left side after cleaning.

Right side before cleaning. Getting that mount (red circle) vertical is a story on its own. There is little to no place to get close to it and remove it. It prevents the manifold to move and getting it in a position like it is now was quite a challenge.

I also managed to get 60mm stainless steel pipe for exhaust mod. I'll drill some holes and put in place in the near future. Finding a perforated one is impossible here. It would save me a lot of work though :/

Also sold the DPF internals for 40€.
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Drive It Like You Stole It
This is coming along nicely. Where are you based?


I equally love and hate German engineering
Thanks. Doing my best. I tend to spend more time doing stuff like this so everything is as it should be. Racing around and doing it quickly leads to mistakes and since I'm not a professional mechanic I take my time. You notice and remember more. Also I don't want to do it twice :D PS I'm to close to corona outbreak.

For cleaning those aluminium surfaces pictured above I used a combination of 1000 grit sanding paper and WD40. It lubricates the surface and prevents the dirt and other debris to go into unwanted places. Don't use anything lower than 1000 as it could leave deep grooves and seal might not compensate. Micro leak could result in blown seal one day.

Afterwards you just wipe the dirt with a piece of cleaning cloth and you'll have a nice, clean, shining surface. Don't use paper towels etc. as they can't provide such good result since they don't absorb that well. I forgot to take the after picture but you can scroll up a bit. The left side has been cleaned in the exactly same way.

After reinstalling both manifolds I put back most of the hoses and other stuff. Among other things I put a egr blanking plate in place. Its on the lower mounting position so when the intake manifold is in place it isn't immediately obvious that something is off. To the trained eye of course. Blanking plate can be mounted to this position only with the intake manifold off. There is very little room for screwing those bolts and the pipe is very stiff so getting the required clearance will be difficult. For undoing these two bolts you'll need multi-tooth hex bit.

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I equally love and hate German engineering
It runs :)
Everything assembled and double checked. Added some coolant that was missing and it appears to run fine. It was cranking for about 20sec (no fuel in some lines) but ran smoothly afterwards.


Happy with the result I went on on the to do list and fixed the leaking rear lights. Left one was bad while right one didn't seam to leak. Applied plenty of sikaflex on light assembly and trunk. The original seal appears well bonded to the light so I didn't touch that one. Time will tell if this needs any more attention.



Leaking left light. The car is in garage for about a week now and there was still quite some water inside that came pouring down once I lifted the trunk.



I equally love and hate German engineering
It was a good day yesterday. Moved the car out of the garage so that means that the work on engine is completed for now. I also finished the right muffler. The pipe fits perfectly and I'm very happy with the result. It only needs to be stuffed with wool and welded but I'll do that once I copy the results onto the left one. I'm still not sure either should I make some holes in it or not. I want it to have a nice deep sound but I don't want to attract any unwanted attention.


Cut at the marked position.










I equally love and hate German engineering
Cut open the left muffler. I got things out way faster compared to the first one I did. I drilled a few dozen holes in the beginning of replacement pipe in order to quiet it down a bit.


Wrapped it in steel wool


Added rock wool. Rock wool has a much higher temperature resistance compared to glass one.

This thing should be called the WOOKIE MOD :D

Welded it up. Welding this thing is quite a tricky process. Thin metal and large gaps tend to make this even more difficult.

One down. One more to go.
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I equally love and hate German engineering
Finished both mufflers and mounted it back on the car. The next day I limped to the dyno and sorted things out. Few hours later I returned home with a shy less of a 300HP and 643Nm. Its a nice ride :) There is a bit of smoke once it passes 3k rpm and that's because the turbo has 240 km on it. Renewing it might save that problem but I'll leave that for another day. We could go higher than 300HP but only after turbo is fixed.




I equally love and hate German engineering
And there is even a video of it. It isn't loud. I was a bit disappointed on that. Come on its a 3.0 V6 and it stays quiet like it is shy or something.


I equally love and hate German engineering
Few months later and I'm getting some progress on AC. First we refilled the system since it was low on gas. Then the pressure sensor started leaking so I replaced that. The AC should be working by now and the AC light stays on after pressed but there is still no cold air. Compressor gets correct voltage so the next thing to do is to replace it. That should be done in a few days. In the meantime I also changed summer tyres. Went for the 255 35 19 Michelin pilot sport 4. I gotta say these tyres are insane in wet. The grip is superb. The old ones were a bit old to say the least (2014) and they were worn out.




Also passed the MOT test so that worry is out of the way :)

In the meantime I'm making myself a keyring. This is just a sample prototype.


I equally love and hate German engineering
Fixed the AC. It was about thine though. It is getting hot. Turned out that the AC compressor failed and needed to be replaced. Quite a tight fit to get it out of there but managed to do it.

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