2.0 TFSI camshaft details or anyone with pump off?

[Ceebl]

Why don't you do a pump proof test? Ground the pressure regulator and see if it makes max pressure and how quickly. You would probably need a scope to measure the pressure build up time. Just make sure you ground the switching side of the pressure reg.

I don't think the pump is the issue, it was also replaced with a new OEM unit about a handful of months ago when I first had issues.
It does make the requested pressure and eventually the peak pressure when it is requested in relation to the revs of the engine but once you open the throttle and put some demand on it the pressure falls away to nothing as I believe the pump is not supplying the required volume of flow therefore the pressure goes through the floor

 

[pablo]

How much is it mapped and might you need the uprated pump?

 

[dervsport]

I don't think the pump is the issue, it was also replaced with a new OEM unit about a handful of months ago when I first had issues.
It does make the requested pressure and eventually the peak pressure when it is requested in relation to the revs of the engine but once you open the throttle and put some demand on it the pressure falls away to nothing as I believe the pump is not supplying the required volume of flow therefore the pressure goes through the floor

Flow problems are more likely to be caused by the low pressure stage. Camshaft wear will result in an inability to make max pressure not flow issues.

 

[pobmk4]

Forgive my ignorance, if I've missed something here as I've only just read through all these posts.
I thought you were just looking to reference info against what you have, but have you actually checked to see if the low pressure side is functioning correctly?
There is a low pressure sensor that gives power delivery issues, if you are making peak pressure but over a certain rpm it's dropping off then as @dervsport has said you need to check that the low pressure side is obtaining the pressure at all times as if it's not correct it will not keep the fuel pressure up.

 

[Ceebl]

It has an autotune map on it, roughly 240-250bhp. I have had it logged by autotune using vagcom and the lift pump is making its requested pressure to within millibars the whole way through the rev and power range, even during the immense drop offs in pressure it is making its requested pressure on the low side.
The high pressure side only makes max pressure if you run the engine up the revs lightly, when its under heavy throttle or load, up a hill say, it will never make peak pressure.
The reason I suspect this drop in pressure is flow related is because it is a plunger based pump and if you are stroking less distance than you are supposed to per revolution you will not pass a sufficient volume of liquid. So when the engine is light it is effectively just topping up the fuel rail as if pumping to a dead head, it can cope with this, however once it is under load it will be requesting a larger quantity of fuel, this is when the pressure instantly plummets to around 30bar, I believe this is because the pump cannot keep up with the quantity of fuel requested and therefore there is a significant drop in pressure.

 

[Ceebl]

The only thing that raised concern to me was the duty cycle on the lift pump at idle was nearly 50% and rosstech themselves recommend a pump be changed if it is 50% or more at idle as this shows wear. However the fact the requested and actual values of the lift pump were within mBar's of each other for the entire run surely means the lift pump is functioning sufficiently?

It seems more likely to me that worn camshafts that are a known issue on this car would be more probable than a lift pump that was logged as doing what it should?

I want it fixed but I really can't justify throwing money at it when its already a high mileage daily if it isn't going to fix it...

I don't reasonably see it being the low pressure sensor as how unlikely is it that it would be scaling incorrectly but still read a sensible value when compared to the requested?

 

[Scuba Steve]

you not asked @AIRFORCE1 to have a look? he is only down the road from you

 

[Ceebl]

you not asked @AIRFORCE1 to have a look? he is only down the road from you

It was with him there for timing, he might be getting it for the camshaft job if I go ahead with this... but as for the measurement the camshaft should be compared to what I am getting, hes no wiser than me at this lol
Given I have taken measurements and it is about 12% worn chances are I will be replacing the camshaft anyway as it is/was only case hardened... regardless of a fueling problem I coincidentally have a worn camshaft so may as well replace it!

 

[Boabybooster]

It was a bit smoky when you accelerated away from the castle roundabout this evening.

 

[Ceebl]

@Boabybooster It does smoke a little when it comes on boost, could be because its pulling timing badly lol... or its just the mileage on the injectors etc... It hardly uses a drop of oil between services so I am expecting it to be something to do with unburnt fuel