42TT

I can't figure this out. The car stock spiked 14, held 12 to 5500. I got a GIAC chip about a month ago and I have been messing with it a little bit at a time because I am so busy. Well, today I have a day off until around 4pm.

The car when first chipped spiked 23 and then immediately fell off to 12. I heard a wooshing noise when it did this, so I bought a replacment DV and made a pressure tester like Schwing's. The OEM DV was fine and there are no leaks. The wooshing noise I have discovered is the N249 bleeding off boost through the DV.

So, I got a MBC. The same one I used on my old 2.0 turbo so I know it works the way I want it to. The car will not run with the N75 bypassed. It gets too much part throttle boost and shuts the engine off. So, I have it in overboost mode as suggested by alot of posts on various forums. I don't think it's really working in overboost mode as I have little to no adjustment.

Right now I have it adjusted so the car spikes 20. It will hold 20 briefly and then take the boost right back down to 12. Sometimes there's the N249 screech / woosh and other times not. I assume the throttle is closing on me. The best I can hold for any length of time is 15psi.

The car is basically a spike and die ride. I am not talking K03 style, the engine barely revs out. At this point I am thinking I just wasted $500 on this software and If I had 3 spare days I would rip this ECU out, throw it in my fireplace and replace it with a real engine management system.

Any suggestions? The car sucks to drive!

(IGNORE the link in my posts, I am trying to get rid of a browser hijacker)

Evan<ul><li><a href="http://www.freeloadmp3.com/">http://www.freeloadmp3.com/</a</li></ul>

TTschwing

Often when you chip, you put additional strain on other components that have to be operating at 100% to maintain 20+ psi boost. Common culprits are the MAF, Coolant sensor etc. If the N249 is pulling boost, it's because the ECU is telling it to based on some sensor input that is not up to snuff. You didn't waste your money (except for the MBC maybe), you just need to upgrade some sensors so the ECU is happy with the information it is getting....

Steve

joe@vwvortex

I went through MAF's, N75's, leak down tests, you name I did it. Check your boost logs and see if you are at 2 bar or over at 3000 rpms. You should be at 1.7 bar (stock program). If you are at 2 or higher - chances are your wastegate actuator is bad or your turbo is going or gone.

42TT

Guys, thanks for your advice. Tonight on my way to turkey dinner I unplugged the MAF to see what would happen. The car feels alot better, but still not 100%. It will hold 19-20psi until 4000 rpms and then it abruptly falls to 12. However, part throttle boost regulation is MUCH improved. Overall power feels better. Top end abruptly stops at 4500.

I replaced the CTS a couple weeks ago, so that's new. I guess a new MAF wouldn't hurt. Any other suggestions? Could my N75 be failing? Spark Plugs?

There are no codes being thrown, so in true VW form I have no idea what's up! I understand these engine management systems quite well, however I am new to the 1.8t so I don't know the corellation between x&amp;y sensors and why they affect boost.

Can you suggest any specific blocks to log? What block #'s are what?

Oh, and can someone please give me an RPM based idea of how much boost their K04 runs? I am not sure when this is supposed to give out in the rev range, but I know that what is happening on mine is quite abrupt.

Any suggestions would be apreciated. You're the experts!

Evan

(ignore the link)<ul><li><a href="http://www.freeloadmp3.com/">http://www.freeloadmp3.com/</a</li></ul>