I am by no means knowledgable about these cars. I am only repeating what I was taught on here and that which I read. And from what I have learned can seem tobe the problem. Now with that being said, I highly doubt there is any problem with your wastegate valve. The only thing I can really see is your dv giving you problems. You seem to have perfect vacuum. Just not boosting as you would want to. What you could try is replacing the yellow spring with the green one with the proper steps in the link I sent before. Make sure connections are correct. The green one is supposed to have you boost peak around 23 psi and the yellow around 18 psi. And I was always under the assumption that the pssshh noise comes from the diverter valve, not the wastegate. So, I am still assuming that you have a problem with your dv. You are supposed to service your aftermarket dv if it is a forge every year. And if it has been 1 1/2 years since you have, more than likely it needed cleaning and new grease. Just make sure that you connect it back up properly.

 

weird... i am not a fan of the n75 upgrade.never done so myself but heard horror stories about how they can cause erratic boosting and just general problems, if you still have the stock one, try putting it back in and seeing what happens. i know it is a pain in the *** but at least you'll know.

 

i pulled the dv back out again tonight. i am a real champ at it now. i cleaned it according to forge motorsports website http://www.forgemotorsport.com/conte...duct=FMCL007PAi guess this dv doesn't use grease or anything, just a cleaning, and i tested it. perfect. not the dv at all. n75j has been in my car for about a year or so. i don't know if i have the stock one.
this is just been crazy, seems like it would be such a simple fix but...wtf.

 

You should try going with the n75h. They are kind of pricey though. http://www.034motorsport.com/product...69d2454dd9f7a7. I was told when chipping to go with the "h" valve that is race.But you can just place the stock back in, and go with an mbc bleeder type. Should have things back to working specs.

 

i don't think it would be the n75 valve since i didn't have any CEL's and no fault when i vag com the car. see what i don't understand is when i had the dv parts install wrong i had 10-12 psi no problems at all with surging. So that mean i had that little nipple hole completely closed off and it had no way of opening unless someone put a turbo in the intake box. lol so that being said, i would if something up in the air box area is bad.
I hate to do it but i might just end up replacing small hoses and such.

 

ok well i replaced some hoses.
1. the hose that go from the nipple on the dv to the fitting right underneath the intake manifold. it was pretty bad the hose was just coming apart. does anyone know if this hose is hooked up to a sensor/switch at the location i just stated. i think it does i just don't know what it does.
2. the vaccum lines that goes from the bottom of the intake manifold (right after the tb) that gets connect into 2 other check valve hoses. i had to replace the T fitting and get a new hose for the one hose becuase i fn broke it getting to the hosefrom the dv. let me tell you this, you break that line and start your car up. you are f'd,my car barely would stay running at idle, driving was fine though. So i had to jimmy it just so i could get to autozone, barely. then after i fixed it, i ran vagged it. lol all cylinders were miss firing and fuel trim was lean. so i cleared the code, and now the car is aok. as far as that
3. i clean and inspected all the other hoses/check valves. good check valves are definitely on the way out, but still good. i put new clamps on the smaller hoses, i.e. the hose that goes from the n75 to the WG.
4. i took off that big thing look like a dv that sits right on top of the big hose that comes right out of the air box that goes down to the "in" side of the turbo. well i took that out and some water came out. wtf is that thing? (FOUND WHAT IS WAS IT IS A CRANKCASE BREATHER VALVE AKA PVC VALVE)I was alittle concern about the water so i clean it as best i new put it back in. I would like to find out what it is.
5. clean the n75 valve looks good
6. took the entire airbox apart, parts are good, maf is good
took the car back to my wife cuz she needed it to get home, can't trust her with the cobra. lol anyways the car had better throttle response and the waste gate flutter came back along with being able to hear the turbo spool. but it still does the surging. f...f...f...ahhhhhhhhhh! man i don't know what i would do without this audi, maybe play some ps3. that would be nice. lol
any more idea's? please...

 

found this diy and think i will give it a try
http://forums.vwvortex.com/zerothread?id=2559817

 

or this way

lets see 10 bucks or 150? 10 bucks and i get to play with a mbc and now look cool when i talk to my dsm buds.

 

$10 mbc dont always work the best. My brother went cheap twice buying crappy ebay mbc's. This turbonetics is only $35 and seems to work well for other people

 

thanks, watching them right now. should i but the n75 in parrel with the mbc or just plug in the n75 and let it hang. (dressed up over course)