Allroad 2.5 tdi air in fuel issues

[roy@pumpa.no]

So there are no meaning in installing the APS-German rebuilt pump again.
They have had it in a Bosch test bench and have no error on it.
They have returned the VP44 to me and added an invoice for € 122.00 for testing and shipping.
I'm kind'a stuck here.
A working but air leaking pump, and a rebuilt pump under warranty with an error but the seller claims it to be ok.
BTW... APS in Germany got the explanation from me that I've given here, AND the Excel sheet showing the driving log.
I assume that they have no clue and are just a eBay broker trying to make the impression of being experts.

I checked the pump, and can't find the big screw that should have tha broken/worn O-ring on the right side of the VP44 (opposite side than fuel inlets).
Picture anyone?

[ametlib]

I totally see your problem here. About the APS pump, in addition to the fault options I gave you, I think we can add an faulty/ sticking advance solenoid and ofcourse the dreadful ECD ontop of the pump ( but I suspect that would have triggered a code)
If you install the pump things can " smoothen out ) after a while, but then I don't know how your engine sounds with a COI of 25 ??
The air leak in your old pump shoudn't be to hard to fix, I post a picture, the screw is no 393, the o-ring no. 392 and you have to remowe at least the crossower inlet to acces it.

2010-07-30_135903_VP44_Explosionszeichnung.jpg

[roy@pumpa.no]

I totally aggree, ametlib.
The ECD is new on the pump (at least it looks new), so I assume that the sleeve for the advance timing piston is worn and causes it to stick.
I don't think that a bench testing can reveal that problem -only eye inspection (I believe that I've read it on bluechip diesel page).

I've no replaced the 392 O-ring, and you're right -rhe cross-over had to be removed.
With my experience, it took no more than 5 minutes.
The first good token is that when I started the vacuum sucker, there were air bubbles for some secounds, followed by a steadily fuel flow. Sometimes a single air bubble, but nothing else.

Before the "392" replacement, I had intermittantly loads of air coming from the pump.
I explained that scenario in my initially posting when the hose to the VP44 was directly into a diesel-can.

Som I'm excited about tomorrow and if the beast fires then.
I sertanly hope so.
I've had the injection pump out so many times now, bleeding and testing for hours and hours...
So if anyone had made an offer "that for £ 1.500,- I'll fix this problem for you" -I would go for it...

[roy@pumpa.no]

I don't know how your engine sounds with a COI of 25 ??

The sound was like a gas engine with wy too high ignition.
A loud hard rackling sound which cuts through marrow and bone...
Like the engine is begging for a bullet in the neck to stop the torture...

[roy@pumpa.no]

Whohaa!!!
The beast started as a dream this morning.
It really seems like that the 392 O-ring was the cause.
The old ring was square in shape and had no flexibility left.
It broke off when I tried to carefully take it away.
The kit didn't have any square O-rings, so I found another round shaped and put on in stead.
Lubricated and put the large bolt back again.
So, maybe case is solved.

[ametlib]

Great, hopefully at least your old Injection Pump is up and running, about the new pump you got me all wrong.I don't belive ther is anything wrong with the advance piston or it's sleeve. In order to make the piston stick in position +25 degrees, the ECU
have to want it out there in the first place. And it's obvious that the ECU rather is trying to prevent this " advance piston runaway" So I'll say the chance that the fault lies in the advance solenoid ( no 424 on the pic. )is more than 75 %
Otherwise ther are debris in the pump that intermittent clogges one of the feed holes into the advance piston

BTW. Sorry Roy I don't answer PM's, but when I can I'll be happy to help through this forum .

[HAWKS]

Sounds like youve cracked it.

[roy@pumpa.no]

Sounds like youve cracked it.

Sorry, I'm not known with that expression..
But the beast starts immediately now without any cranking.
When I'm recalling the last two years, there has been a little cranking to start it.
We also have a 2000 Passat 2,5 TDI 4-Motion and I have noticed that it starts easier than the Allroad did.
Now, they're equal.

But how to test the APS-German rebuilt VP44?
Put it into the Allroad again?

The Germans did provide a test sheet that shows everything's ok...
And a bill for testing: € 120.00

[ametlib]

You have already tested the pump, it's just pure luck the cyl. heads are still in place. Send APS an e-mail (in German) and explain the problem, just tell them there are A-something wrong with the Advance solenoid or B- debris in the pump and send the logs too . It's really no good
for APS to get this negative publisity on the internet, so I'll guess they will fix this, but don't quite understand the problem. ( never underestimate how bad the Germans are in English )

[HAWKS]

Sounds like youve cracked it.= looks like you have fixed it, well done...
congrats.
Now to sort Ze Germans out over your new Caput pumpen.