ALH 11mm pump power loss at 2k RPM

Hey y'all just finished up a diesel swap on a mk1 Audi TT with an ALH. We have it running, timing is like spot on, injection Quantity is at 4.2 roughly and now were stumped... When we are driving the car seems fine in the neighborhood but when we get onto a main road and rev past 2k the car just won't pull very hard. the engine is definitely revving as it gets louder but just no power. The only thing we've changed since we had it running was the injection pump to swap it with an 11mm one. we tried replacing the usual suspects( fuel filter, retimed everything, hammer mod, etc) we do have a glow plug fault code but i would assume that doesn't affect this. the only other code that pops up is when were driving it will show a code for "timing deviation" has anyone else ever had any issues with this? thanks for the help in advance!
-Alec

The 11mm pump often has timing issues when paired with larger than stock nozzles. They seem to have fairly low case pressure set from the factory so often need it increasing to hold timing at high power levels (the timing solenoid uses fuel pressure to control the timing). I've not seen one throw a code for it though - usually it causes a shudder or shows up in the logs. Do you have VCDS?

Fix here: http://forums.tdiclub.com/showthread.php?t=437160 Try small increments (0.2-0.5mm) and see if it improves. You don't want to go too far though.

Mikkijayne said:

The 11mm pump often has timing issues when paired with larger than stock nozzles. They seem to have fairly low case pressure set from the factory so often need it increasing to hold timing at high power levels (the timing solenoid uses fuel pressure to control the timing). I've not seen one throw a code for it though - usually it causes a shudder or shows up in the logs. Do you have VCDS?

Fix here: http://forums.tdiclub.com/showthread.php?t=437160 Try small increments (0.2-0.5mm) and see if it improves. You don't want to go too far though.

Click to expand...

just decided to run some diesel purge through it and while i was doing hat checking out vcds. I noticed when i rev above 2k rpm the p1248 code appears. I wipe it and let it idle and it goes away but then ill rev it again and it appears again.

so how exactly do I do this? i don't take off the nut ontop?

If there is an error with the growth of the revolutions and the lead angle does not reach the requested one, then the pressure of the case is lost. There are several options to solve this.
1. put the booster pump in the tank.
2. Raise the internal pressure
The norm is 1bar of pressure per 1 mm of the plunger at 1000 pump revolutions (= 2000 engine revolutions).
But I'm working with 27 bars for high performance)
3. replace the Blade pump in the injection pump.
Sorry, translated via Google

FYI, here's a little more detail on the problem...
http://forums.tdiclub.com/showthread.php?p=5287418#post5287418

Check the little plunger on the pump itself. you take it out with I believe a 22mm socket, it has the wire going onto it. The rubber will deteriorate, especially if the pump is left to sit for a while and not used. When it deteriorates it will close giving no fuel. Had this happen a few years back. No power over 2200 rpm. This fixed it.

UPDATE!! Huge thank you to MIKKIJAYNE! that was exactly it! we removed the valve itself and noticed that it was stuck completely open! we popped the one we had laying around from the old 10mm pump and plopped it in and it made a huge difference! The car actually drives as it should! Thanks to everyone who responded!