2005 TDI Passat Limp mode with multiple codes. Replaced n75, CHRA, VNT actuator, boos

I am having a helluva time with this car and any help would be greatly appreciated. I have been getting limp mode which was previously intermittent and now is persistent and constant. If I clear the codes with the basic trouble computer they come back within 3 seconds of starting the car up. I have not used VCDS yet but have a friend with it who will scan the car next month when he is home if I cant solve the problem before then. I have replaced the CHRA (took turbo apart to clean VNT and saw the fins looked like something had gone through them and chewed them up a bit), the vnt actuator (Kermatdi replacement), n75, boost sensor, vacuum lines, and disassembled and cleaned the egr, cooler, and intake parts.

-The boost sensor is a bosch sensor from Napa
-The N75 I bought was this one: http://www.ebay.com/itm/FOR-VW-TDI-...-Jetta-Passat-Golf-Beetle-00-06-/281840365293
-The CHRA was from Alamo Turbo in Washington. They are legit, not a cheapo knockoff
-as I said Kermatdi VNT actuator

I am getting the emissions workshop message, P0245 "wastegate solenoid low a", P2102 "throttle actuator control motor circuit low", P2100 "throttle actuator control motor circuit/open", and P0299 "Turbocharger underboost"

I am a poor grad student and have blow all of my expendable income trying to have a working car. Please help if you can, I can't afford to throw many more parts at this car

Danielliam said:

I am getting the emissions workshop message, P0245 "wastegate solenoid low a", P2102 "throttle actuator control motor circuit low", P2100 "throttle actuator control motor circuit/open", and P0299 "Turbocharger underboost"

Click to expand...

The 1st 2 could be wiring problems, bad connection, broken, frayed wires, a bad 109 relay, even a fuse.
I could not find P2100.
The 299 could be a boost leak or from the "wastegate solenoid"
Have you checked the fuses inside the car and above the battery?
Check & clean the ground connections?
The one under the battery tray has been mentioned many times as well as one in the car, left side of the dash in the kick panel.
If the ECU is under the plenum and water gets in there that could cause bad connections.
The ECU should be the last thing to replace unless someone knows there's an issue with your model.
A scan with VCDS might help, it could show and test more.

That car has no relay 109.

Let's back up a bit. Generic OBD2 scan tools suck, especially on Volkswagens. You are going to get a bunch of gibberish that will have you spinning your tail.

You really need to get a proper scan tool to diagnose your car. And what is a CHRA?

Any low boost DTC will not show up until you drive the car. A proper scan tool will let you do an output test on things like the VNT control (N75) and other things. Your description is vague at best, so I am not really sure what we can tell you at this point. Get a VCDS, and we can get somewhere most likely.

My guess is you have a wire problem to the N75, a bad intake flap, but those are just guesses.