I've tried searching other places but for some reason my computer is blocked form almost every audi forum, its been giving me weird internet issues like that for some time. Short back story, stock k03 was definitely on its way out bad. So I installed a new K04, runs great.. only concern is that under wot at about 5k rpm it hits like boost cut or spark cut or something.. I'm assuming i may be over boosting so i've been staying out of it until i can get it returned, which is a whole other story all together. Is this a common issue? what is a fix for this? Also, after hitting that wall at about 5k my car has now developed a weird moaning/grunting/cow/whale noise under the hood. At first it seems extremele random, but now the more i play with it the more it seems like it makes the noise under tip out throttle, Its specifically bad cruising at like 70-80mph and is almost a consistant noise that i can modulate with the throttle, i can almost feel the noice in the floor, or pedal, It almost sounds like a diaphragm is going bad or something, anyone heard or this and may have a common fix? Its a MFer to diag since it will only do it underload, and i cant get it to do it by powerbraking the vehicle. 3rd question is just something thats kind of been on my mind and bugging me, I cant seem to find the map/boost sensor to save my life. Again i cant get access to any good information cause my computer hates me, but what i have been able to gather is that it should be on the factory intercooler. I don't see it there, or anywhere for that matter. any suggestions, besides open my eyes? All and all i think thats pretty much it so if anyone can help out it would be greatly appreciated

 

did you also add software for the k04? You should just call justin at urotuning he'll set you straight.

 

First you need a tune ASAP. You are more than likely overboosting then the ECU is going into limp mode. Also I would HIGHLY suggest you buy a boost gauge. The moaning could be a lot of different things but if you have the stock DV I would start there as it's probably dead. Last is you have a 99 so no you do not have a map only 00-01 A4's came with the MAP on the intercooler which makes it possible to do the diode mod.

 

I dont know if you have solved your issue but....

97 to 99 audis do not use MAP sensor. AEB engine codes only use the N75 valve for boost control. The N75 valve is located at the turbo inlet pipe. You definately need to tune you car if you want to got wide open throttle with it. a K04 is slightly bigger than a k03, therefore flowing more air throughout the rpm range....at 5k rpm its where it could hit overboost and cut you off.
The moioaning could be your turbo going bad...did you buy it new or used? thats how mine sounded with the the turbo took a dump on me.
Do you have the CEL on? if so have it scanned at autozone for free and get back to us here.

 

If your raising the boost, you might wanna get a 5 bar fuel pressure regulator to keep the fuel coming at high rpm's