i replaced my stock K03 in my 98 1.8tq with a K03s and am having an overboost issue. After some research I have found out that the actuators on our B5s open with less pressure than on the B6's. This explains the overboost issue.

Can I loosen the wastegate actuator enough to compensate? Or do i need to throw on the old actuator?

 

I'm thinking about throwing in a MBC instead of messing with the actuator. Ideas?

 

how much boost is overboosting??

 

Enough to kick it into limp mode

 

Grab yourself a TT225 diverter valve and tune your ECM. Don't bother messing with a MBC unless you have to.

 

I have a Forge 007 DV now... Where do I re-map my ECU for the K03s??? Some say it's not needed - I disagree

 

So I tested the wastegate actuator pressure today. It actuates around 11psi, so I'm guessing that even if I would have loosened the wastegate it wouldn't have solved my problem...

Here's what I don't get, If I disconnect my N 75 it still overboosts and kicks into limp mode.

 

The N75 controls the wastegate, so if it is unplugged, it will go into limp mode to prevent damage. Any vacuum leaks around the N75? Have you tried swapping it with a new one?

 

did you make sure your stock boost controller is hooked up? i had this problem on my old b5 and that fixed my problem.

 

I thought the way to see if the N75 was bad was by unplugging it. This should actuate the wastegate by pressure off the compressor right? If i'm right, the wastegate would then open at 11psi (according to my pressure test on the actuator) Is that too much pressure on a 98t q?