haha, I chipped my car @ Autotrim in gothenburg, so don't expect any help there except for the suggestion to a checkup.
Otherwise, I'm very satisfied with their service.

But what troubles me is that it works as it should sometimes, and that is on 2nd gear...maybe I should try with a N75J, i didn't know there was so many varietes of the valve.

Edit: What is "surging"? :S

 

I think that surging is the unability to hold correct boost pressurewhich can lead to overboost in the middle revs with moderate throttle leading to choppy acceleration etc. At any given acceleration it should be somewhat linear not like a sinuscurve which tends to be the case.

EDIT:
Yes it seems to work in the higher revs but on higher gearat around 2500rpm when giving full throttle there seems to be an overboost most of the time going immediately to 1.5bar and sometimes the car stalls and pressure drops to 1.0bar and then immdeately up to 1.3 and seems to go between 1.1 and 1.3 up and down. This was exatcly what it did the first time it happened and also after the exchange with the new N75 valve when it "broke" too.

 

its gotta be the tuning then. over here in america, we have 3 main tuning companies and each of them have their own n75 valve that they work best with and using the wrong one often causes limp mode or surging.

there's a J, H, F, and C n75 valve, and there might be more. Trying all those is gona be expensive, which is why i suggested bypassing it and using a mbc.

 

Yeah I will try a valve over at boostvalve.com if the "J" N75 valve doesnt fix it. But as of now I am eagerly waiting for my J valve to drop in my mailbox :=)

 

Moxin, wanna tell if it works? I'm eager to get one myself :P

Edit: Anyone know the serialnumbers on the valve-varietes?

 

Got this from another site, and I see that the first three numbers doesnt match but according to some other pages the part number should be identical except the Letter at the end designating the version. I will dig a little bit deeper.

Btw I got my VAG-COM today and I had a "Intermittent voltage error N75 boost control valve" I have resetted the Error codes andI will drive around and test again. All other things checks including the Air Mass Meter.

I think the intermittent error occured when I disconnected the N75 and started the engine, doing the same test as you Zoid. Il report.

 

Sounds great =) thanks, man.

I read somethings thatan brokenair mass meter can cause quite some problems and that an open air filter can cause the AMM to break?

 

Little update:

Checked my newest N75, and it was an "F" model, i THINK that the original one was a C though.

My car was on service today, and I told them NOT to mess with any electronics because of the tuning.
However, it acted as it did in the beginning, with the pulsing boost pressure.

 

open air filter can't cause anything to break

 

That's what I thought. There is much rumor ion the swedish forums that it breaks down the air mass meter (the thing with the wire inside that wars up to measure the amount of air that's passing to the engine) because of the filter-oil that sticks to the wire.