Just thinking about an ECU remap

[usmangti]

Its possible the diverter valve has gone as its having to hold higher boost now, Get a rev G and changing its quite easy. There are guides on the forum and I managed to do it, and I'm a novice when i comes to mechanical stuff. Its basically remove offside front wheel, remove some of the plastic liners , unplug the DV and remove the 3 torx screws. Fitting is the reverse.

[rashg60]

Thanks Usmangti.

I have now replaced the air flow sensor and the car goes much much better, i.e. much smoother in every gear like it used to be. However, the power surge that I got after the Stage 1 map still isn't there. I have therefore ordered a Rev G DV from VW, which should be here tomorrow. Hopefully that should cure the problem.

If this still doesn't do it - any more recommendations/ideas?

[usmangti]

Sounds like DV, If the DV is torn then it will be losing boost therefore wont have the surge you are expecting. Read some guides on here as on first glance the DV may seem fine.

[rashg60]

Where exactly is the DV located and is it easy to reach once the passenger side wheel has been removed?

[rashg60]

Replaced the DV now.

Again car feels much better but it's still lacking that power surge.

[usmangti]

what was your old dv like? Also I find when I don't drive mine much or without giving it the beans it does start to feel flat. Get it nice and warm and go for a good drive, going through the gears. Nowadays I make sure to give mine a good blast in a few gears daily and I have not felt it go flat since.

Check your oil levels too.

[rashg60]

To be honest the old DV didn't look too bad - it wasn't split or anything. In fact it looked as good as new. I replaced it with the new one anyway just in case.

I have emailed R-Tech re. these latest developments and will wait and see what they say.

[usmangti]

Did you split the DV to the diaphragm? That is why I mentioned it may have looked ok. What rev was in before and after?

[Scottymon]

Replaced the DV now.

Again car feels much better but it's still lacking that power surge.

Has it had a few tanks of vPower / Momentum?

What are we comparing "the surge" too?  300lb/ft+ should definitely feel noticeable though.

[rashg60]

I took it all apart and everything was intact. It was a rev c - I actually replaced it with the rev d in the end.

[rashg60]

I've only ever used shell v-power fuel since I've owned the car.
It was 247bhp with 292 torque.

[rashg60]

Feels much more like standard though - so nothing compared to those figures.

[AJP]

You really want to get the car back on R-Tech's rollers to get a more accurate idea of how much boost and power you're losing.

Incidentally some people find the piston rev D to leak, by design, from new. Not to the extent that a split diaphram dv would, but maybe that's why things seem better, but not quite 'there'.

The consensus is that the rev G (diaphram) is the one to have over the rev D (piston). Your rev C was a diaphram valve. My info on the specifics of the different valves may be wrong (and people, please correct me if I am) but it's an idea at least to try the rev G.

[Scottymon]

You really want to get the car back on R-Tech's rollers to get a more accurate idea of how much boost and power you're losing.

Incidentally some people find the piston rev D to leak, by design, from new. Not to the extent that a split diaphram dv would, but maybe that's why things seem better, but not quite 'there'.

The consensus is that the rev G (diaphram) is the one to have over the rev D (piston). Your rev C was a diaphram valve. My info on the specifics of the different valves may be wrong (and people, please correct me if I am) but it's an idea at least to try the rev G.

The Rev G is definitely the best at holding boost, and probably the best to use to fault find.
Mine kept tearing (probably cos turbo was getting too hot) went through 3 over time.

Not an issue on K04, Rev.G all day.

[rashg60]

I've already emailed R-Tech this evening so hopefully it should be back down there so they can test it.

I'd rather not spend any more money on parts just to eliminate any further possible causes.

Thanks for all your advice so far guys. Will keep you posted on any updates.