my z6 motor has a 14b turbo. when i had my zc in it, i didn't experience this problem. now it doesn't stop building pressure. i don't the wastegate isn't stuck either.

 

If its a internal WG they usually creep. Check the signal line make sure its good. Did you add a boost controller to it? Save up for a Tial

 

check the wg to make sure it's opening

 

here's the deal. it is internally gated. It didn't do this before. i got under the car and used plyers and the gate opens like it always has. as far as boost creep, i've hit 15 psi on one hard pull, it didn't slowly get there. as soon as it build boost, it just kept climbing all the way up. the only things that have changed are the fact that i put on an air filter, and the z6 only really has one good vacuum source. my zc had a bunch. i had one dedicated to each of the map and blowoff valves. now, everything is on one. that's what i mean about the engine swap.

 

If you're worried about over-using a vaccum source you can buy/make a vaccum manifold that runs off the brake booster line.

 

yep here's my setup

 

just cause you can open the thing w/ plyers, doesn't mean it's opening when ur driving it

 

grab a bike pump and hook it up to the wastegate line. if it open then you know it is the line or it is just creeping like internals do