2003 Jetta TDI issue..
 

Hello

I recently bought a 2003 Jetta Diesel 5-speed. Ever since I bought it there has been a check engine light. I finally got around to putting it on my machine and the code that pops up is P0299 and that says it has a turbo underboost. The problem i'm experiencing is loss of power. After 3k RPM, i feel that there is no boost. Other times at 3K RPM there is a lot of boost and I can feel it. is that the Wastegate valve on the firewall? I discovered that there was two of those valves, one on top of the master cylinder and another next to it. Help????? could that be the problem? if so, which do i replace?

I changed the wastegate valve-N75 valve and still no difference..