EGR Cooler Problem

[snapdragon]

I have had EGR insufficient flow errors for over a year and they have got a bit more frequent. I thought I'd begin giving it a clean today and it is a pig of a job.
It has done nearly 250,000miles and so I expected it to be blocked with coke/soot.
I was using this as a guide:
http://www.vwaudiforum.co.uk/forum/s...GR-Valve/page3

I removed the upper manifold and throttle.
The throttle was a bit dirty but much cleaner than I expected
I then removed both lower manifolds (mainly to access two bolts, otherwise just the left side would do) Many items need to be removed to get to all the bolts and even then it is difficult and requires an assortment of bits.
The lower manifolds were also cleaner than I expected and then I saw from labels on them they were replaced along with the flap motors in late 2010 just before I bought the car. = Thanks to previous owner.

I removed the EGR vacuum mechanism which uses XZN socket - thankfully had a set from removing the seat to do bluetooth. Upon removing the EGR mechanism from the EGR cooler flap mechanism, I found a loose plate inside about 25mm diameter. It was just laid there and was fretted around the edge and had obviously been bouncing around. I checked all 6 intake runner flaps were intact which they were and then realised it is the EGR cooler bypass flap and it had come off the shaft and would move around and sometimes block EGR flow. It is not obvious how it was fastened to the shaft, but there are no corresponding screw-holes on the shaft for the holes in the plate, so I think it was spot-welded. I also found the shaft rather sloppy in it's bushings and this must have contributed to the flap breaking off.

So not what I expected but a new cooler bypass mechanism 059131063D (20 on diagram) is on it's way and I will strip down more on Sunday and hopefully clean and see what gaskets and screws need replacing.

[snapdragon]

Gosh 2 days of struggle to get this EGR off.

This was a big help, page 1 & 11 (photos and description) & my question at page 12.
http://www.audi-sport.net/xf/threads...1/#post2118561

I had to cut a small hose on the right of the EGR and then it should just pull off but it 'plugs' into the engine block with two metal union coolant pipes with o-rings on and these corrode to the block and get fouled with what I assume is silicate from the coolant. It took a crowbar and some rubber padding against the right cyclinder head intake face to pop it out.

Now I have it in the house and await the new part (I ordered a J suffix and have a D - and since found that is for the CABA engines not ASB, so hoping it fits - looks identical on the photos.

All the VAG EKTAmparts diagram websites seem to have gone offline which has made it harder.

I have uploaded a video that shows how much slop there is in the mechanism - the top bearing/bushing seems missing and light can even shine through and smoke has clearly been coming out as everything is black and smells of exhaust fumes. Maybe worth checking for this excessive play and soot in situ if you have this engine.

Why are all my photos upside down?

[snapdragon]

Well, it took a long time, a lots of puzzles, but the new EGR cooler bypass valve was fitted. It was £122 trade plus £75 for sundries, coolant, seals, pipes and unions etc.. also includes a new engine cover Audi emblem (£12) as the old one was lost before my ownership.

To keep the cost down, I didn't replace the seals between the lower manifolds and head and lower and upper manifolds as they were still quite deep and soft, I just cleaned them.

Now I get the engine light on and the same code as before but instead of intermittent it is every journey, but not a waste of time as the peformance is better with all that greasy soot gone, 2-3 valve ports were more than 50% blocked. I also removed that butterfly plate and stopped the smoke leaking out of the part I replaced. The EGR gas should now be cooled when it is supposed to be.
I still get the insufficient flow code but I did damage the thin vacuum pipes in several places as they had gone really brittle. I joined them together with red heatshrink tubing (see photo) and if the ends snapped off, just stuck them back into the rubber joints. I will order new ones but looks to be £90 for the set of 3.

[Pug]

Despite people not commenting, I think a lot of people have been following this thread. I have.

[Mechcanico Lee]

Yes I have been following it .

Snap , go into activations , active egr control and watch air mass reading drop , usually air mass reading will drop by half when egr open .

Does the 3L have swirl control is this operating ok ... again go into activations see if air mass drops when activated , swirls butterfly's normally closed at idle to get air speed up ,and open when revs over 2000 rpm or so

Egr causes so much trouble with the diesels .... manifold Black Death , ports blocked to death .....all the diesel cars I've as a power upgrade blank off egr and write out of the programs script .

Better mpg , runs better and no Black Death anymore

[snapdragon]

Cheers fellars!
I just went out to do Lee's tests and found another crack in a vacuum pipe it even snapped again when taking it off!
Attachment 14029

Attachment 14030

So I repaired that with some lawnmower fuel tubing and went for a drive and no more engine light or code so it must have been the fact there was no vacuum.

Attachment 14027

Lee, how do you activate EGR? If I go into output tests, the engine stops at the first test as that test is closing the throttle valve. The only way round that is to triple-click NEXT/ACTIVATE so it just does a big stumble and advances to the next test. If I get to the EGR test, I can't see the measuring blocks without closing that window down. I must be missing something.
In any case, actual EGR is alwayssignificantly more than specified...even before I started all this, maybe the VCDS labels are transposed?
Do you have any advice about how to activate EGR and view MAF?
Thanks.
Attachment 14028