My uncle and me just got done upgrading the turbo on my 2000 a4 1.8t. At first it ran good at 12psi. so i hooked up the n75 valve and it ran at 20psi and settled at 16psi. until the charge pipe blew off the front mount. so i hooked it back up n it ran good agaian until the wastegate line came off n it would only run at 5psi. So i took off the n75 valve so i can put it back to 12psi and now it still only runs at 5psi. Does anyone have an idea to what could have happend.

 

More information about the car. Like is it automatic or manual?What turbo did you update to and what other mods do you have!

 

turbo used? setup is needed to help

 

it is a 2000 audi a4 1.8t automatic wit a x02 racing bov a godspeed frontmount a ko3 hybrid turbo which is stock hotside and a t3 compressor side a 2.5 inch downpipe back exhust

 

I would start with boost leak test.

 

if you are just running off the wastegate, you wont go above 5psi.

 

I tested the wastegate with a hand vacume pump n it didnt hold any but im not sure if its suppose to the problem started right after the line fell off the wastegate. I dont know if that would make it go completly close and break a seal or not.

 

so your saying with out the n75 valve and the line goin stright from the turbo housing to the wastegate it will only run 5psi cause the place i bought it at said it was set at 12 psi and it did run that at first. Then with the n75 valve it ran 16psi like it did with the k03 but after the line blew off the wastegate it wont run over 5psi the bov was sounding alot louder then usual and longer sound to idk y

 

No pressure on the wastegate will make the bypass not open. Since you didnt say anything about a massive spike, it should be fine. The wastegate should be closed and firm when you are in vac or motor is off. The psi should be set to 5psi on a stock wastegate

 

Yeah when i bought the car it said it was stock but it ran 16psi all gears and with the new turbo it came with its own wastegate. we had to modifie the bov and intake for the new turbo so the bov is one line in with a block plate on the side line and a horn on the other side and top small line so i dont know if the wastegate bad are the bov seals are shot are what im not all that great with audis