Hey everyone, this is a pretty long story so I'll just skip to the end.

The gauge in my car reads 1.6bar at WOT but logs show regular boost. During a WOT pull, logs show throttle body opens at around 50-60%. Car is not really moving so I know it is definitely not over boosting.

There are no boost leaks. I had few and fixed all of them some days ago. I had the plenum, throttle body, y-pipe etc out afterwards.

What could I have possibly messed up that would cause throttle body and boost issues like this?

Thanks for any help.

 

I just realized that it throws a soft code, p1255, so it is over boosting.

 

replace your pressure sensor(Map sensor)

 

Take a look at all the sense lines to the N75 valve especially the one coming from the intake...

 

Did you do a throttle body reset?

 

So I removed the n75 and pressure tested the line that connects both actuators. No leaks.

Doubt it's the pressure sensor but I went ahead and ordered one to replace along with the n75.

Yup, that was my first guess since I was there zip tying stuff but turns out no issues there.

Yes.

I went head and ordered n75 and map sensors. At this point the car has no boost leaks, no leaks past the n75, both actuators are working... it better bet the n75 or map sensor

 

You don't have a Durametric? You can trigger this valve and see if it click.....(or PIWIS or PST2)

 

I didn't know you can do that via a Durametric. Will the n75 really "click" enough to hear it?

 

Yes!

 

Well, issue solved. It was either the n75 or MAP sensor. I just replaced both since they were under $30 each. Plus 15+ year old car, might as well replace them at this point.

 

Happy for you! Good job!!!!

 

It’s usually never that easy. Nice job