I think you misread my last post, wasn't bashing the seller of your k04. I was just saying I was surprised they didn't go with the more realiable supplier like the one you got. As far as my franken turbo, yes that is my thread. Turns out something hit the turbine and chewed the **** out of it. Back on topic: There are tons of people running Chinese turbos, and I would say a majority work fine for light or low mileage use but you will only ever hear people say when something's goes wrong.
Your turbo might be fine just move the wastegate flap to see, if not just get the replacement he offered. Turbos are actually pretty easy to replace

 

Today, my mechanic and I were able to hook up my old K03 to see how much PSI it took to crack the wastegate, roughly 5 PSI. Then, I hooked the compressor to my K04. At first, I was pushing 5 PSI and nothing, but just above 10 PSI there it went. I then used my fingers to manually open the flapper a dozen times or so, from that point on it only took 5 PSI to crack her. Before conducting this test BTW, I ran a boost/vaccum leak test by using the compressor and everything appeared good.

I wasn't able to test drive it though because we're also installing a new MAF, and stopped mid-way through because we were thirsty for a barley pop, that and it was a long day. We'll pick-up where we left off early tomorrow morning, at which point once the MAF switch is complete, we'll also be installing my new Valeo Single-Mass Conversion Clutch kit replacement. Yeah, I cheaped out on the clutch rather than getting something sweet, but granted I just bought a turbo, MAF, software, 5BAR, and windshield wiper tranny, there's only so much dough available at any given time

Once we finish the MAF and clutch tomorrow, I'll give it a spin with my fingers crossed! Will be checking back with another update.

 

5psi sounds about right. Hopefully it will run perfectly now that you messed with it. The clutch is a pain in the *** btw

 

I was able to adjust the wastegate to crack at 5psi, now my boost in 1st/2nd spikes at 25psi, but doesn't appear to be troublesome since I'm able to just "FLY" through those gears, far more powerful that this tune on the K03 no doubt. In 3rd/4th/5th I'm more around the 20-21, and the best part of it all is that it's not longer hitting 30 at the moment, and it's actually tapering down unlike it did before messing with the wastegate. Just to be clear, I never adjusted the wastegate per se, but rather just forced it open by hand a few times. My fuel trims are good as well which is also a plus! At first, it wouldn't open until at least 15 psi, but it's now consistently opening at 5 or so psi. I'd like to give a huge shout out to those that helped me out with this issue! Props!

I do still have a MAF code, and even after installing a new OEM one this morning the engine light stayed off, but while driving it with Vag-Com hooked up, the MAF was still being overworked unfortunately. With that said, I just put my old one back in to save the $100 at the moment. In 4th/5th at higher RPM and WOT, the car was hesitating, loosing power by jerking/shuddering. I didn't have any boost/vacuum leaks when I pushed air through the system, and everything in regards to the logistics of the N75 valve were good during the drive according to Vag-Com. I was driving the vehicle while my mechanic rode in the passenger seat analyzing the values on Vag, but nothing during our in-depth run revealed inconsistencies with the N75 so it appears there's no issues there. We ran 1/2, 3/4, and WOT during the run, so I believe we did a very thorough job at making sure the boost expected and/or received is accurate.

Since the MAF values per Vag-Com didn't go away with a replacement, I'm thinking there may be a need for a larger one, but would like some input on this? I contacted a performance shop near my home that runs GIAC software, but he said my 2001 shouldn't require the VR6 or TT225 MAF, and it could actually create more problems. Maybe I just need to go the MBC route and tune the psi so that it doesn't even touch 25, even if it's only in 1st/2nd gears? But, a spike of 25psi is not that big of a concern though right? Isn't more or less where it's holding? Especially through gears where the RPM cycle is slower? (i.e. 3rd/4th/5th) where I'm at 20ish? Either way, the power is awesome, and by no means is "similar" in any way, shape, or form compared to the very same tune on my K03! It's night and day at this point with the K04/5BAR upgrade.

One thing I'm going to do for sure in regards to addressing the bogging/hesitating in 4th/5th during high RPM's is purchase an after-market silicone TIP. I don't feel like spending $200 on one from APR, although it does have wire inside that they claim would never collapse. With a K04, I'm thinking any decent Silicone should provide me with what I'm looking for compared to stock.

Here's what I'm looking at: What do you guys think?

UPGR8 96 01 A4 B5 1 8T 96 05 VW Passat B5 Turbo Induction Intake Inlet Hose Kit | eBay

I think the shuddering/power loss that only occurs in 4th-5th at higher rpm's would be because of my stock 250k mile inlet pipe cannot handle the air-flow at such high RPM.....

 

25 psi is too high IMO, you should put a mbc in parallel to the n75 to reduce the spikes. The silicone TIP looks fine, I don't think it will do as much as you might expect but it might do well. Your maf size should be specified by the tuner, for example my tune calls for a 3" maf

 

My tune doesn't, the only K04 tunes I've seen that do are for the larger injectors. Anyway, maybe because of the 25psi spikes, that's why I continue to get the MAF code, even with the new OEM replacement we temporarily installed and ran this morning? I guess it would make sense. Also, maybe the same 25psi spike is why the TIP would be collapsing? Thus, is the reason the shudder/bogging only occurred in 4th/5th gears, where the highest RPM range is cycled the longest? Like I also said, 1st/2nd hit 25psi, but the car just rips through those thus not affecting the TIP like 4th/5th, and possibly why I don't feel the issue during those situations? I could do some searching on the best MBC (and already have a bit) but now that I have your attention ......which one is the best bang for your buck?

When it comes to setting the MBC, if you set it at lets say 21, you won't even get spikes over that? But, it should still be capable of holding at 21 still correct?

Edit-What part about the silicone TIP do you think it will not do too well at? All I'm looking for is a TIP that doesn't collapse with the added flow/boost of the K04, especially during higher rpm's like I "believe" my stock one is doing, resulting in the shudder/bogging/PSI fluttering that's going on.

 

I'm just astonished as to all the issues I've had since installing the K04 on the same software I had with my K03, disappointing to say the least.

Well, I just drove the car again and it's still overboosting at times. Although we didn't adjust the wastegate, I don't feel as if that's the issue anymore. Like I said already, it wouldn't open the first time we pushed 5psi into it, but rather took 15psi. After that first shot, it opened at 5psi repeatedly, so I'm ruling that out as being the sole reason for the overboost. Although, the boost is at least bleeding more so than it did before shooting air into it, so I guess it wasn't a complete lost cause.

I also ordered a boost sensor, but only as a last resort, we'll try putting it in since it's easy to do, but I have a feeling we'll be returning it because we're not confident it is the root cause either. My mechanic is now thinking the TIP is a primary cause of the shuddering/power loss, and overboost, so once I install the new silicone one I just ordered, I'll give an update. To change out the TIP, we might as well put another N75 in for the hell of it, even though Vag-Com didn't reveal any issues with how it was functioning, at this point it's virtually trial and error......

The thing is, on my way home from the shop which is about 20 miles or so, the car wasn't overboosting like it has been, was holding at 20-21 in 3rd-5th for the most part, and bleeding boost accordingly. I just drove it to the gas station which is only a couple miles from my home, and once again it was overboosting near 25ish on and off. With that said, whatever is going on is "inconsistent."

I did call ST and spoke to Oliver, he was pretty much out of ideas too, and pretty much said he doesn't think it's software related at all, go figure. At this point, I don't know what it's for sure either, but my hopes is that the TIP is collapsing, resulting in the overboost and hesitation/shudder. Sigh....

 

A mbc will control overboost spikes, as it reacts quicker than the computer controlled n75. Your hesitations may be caused by your spark plugs, that always made me jerk like crazy. Buy yourself some bkr7e's gapped at .028". I other thing I did was delete my icm and upgrade to 2.0tfsi coils and that stopped all misfiring on my current setup. I don't think the TIP would do anything honestly.
I really have no clue about your maf code, I've never heard of that before. I would just clean your sensor and see what happens. I guess the boost spiking to 25psi could cause the outflow

 

I already put in a new OEM MAF and drove it around for a bit this morning, however Vag-Com was still pulling up a MAF code, most likely from when I occasionally boost 25+, it's simply too much for the OEM MAF. Once we saw that even the brand-new MAF wasn't revolving the poor values on Vag-Com, we just took it out and put the old one back in to save $100 in the meantime. I'll probably want to use that $100 on something else until we can 100% solve my overboost/MAF fault issues. My mechanic is pretty set on the TIP at this point being the cause of the MAF trouble, and the way he explained it to me it makes sense. IMO, if the TIP were collapsing (very possible being 250K miles old) it could very well throw off the numbers/values by not letting enough air in and out through the sensor, causing a code for air flow and appearing to be a bad MAF, when in reality it could very well be the TIP affecting other components. Like I said, we've tried pretty much everything else to nail down the overboost & MAF trouble codes, so we'll put in the new TIP silicone pipe when it arrives and go from there. With the sensor not reading correct in/out air flow, it's very well possible that it can correlate with overboosting and incorrect air flow values according to my mechanic, and also according to some information I found on other forums with various individuals that had similar issues, but of course it isn't a "for sure" thing at this point. My mechanic went into further detail than described here about the TIP being the culprit, however I cannot honestly remember all the logistics involved. While we have the TIP off for a replacement, we'll probably double check all the N75 lines at that time, and also put in a used (good working) N75 valve (OEM) that my mechanic has laying around, at this point why not try it right? lol.....

Only time will tell if the TIP theory my mechanic believes in solves the problem. When my mechanic explained all the logistics with everything a collapsing TIP could affect, it made me a firm believer to say the least. I'll tell you one thing, after all the hassle I've already been through trying to pinpoint this BS, my fingers are definitely crossed with the whole TIP replacement.....boy let me tell ya!

 

Go for it, it can't hurt anything to put in a new tip. Again I doubt that's the problem but I've been wrong before lol.