P0234 code came up today (turbocharger wastegate malfunction). What does this mean? Im running on stock boost,no mbc. Is it overboosting ?

 

Did you do a search for that code yet to see what it meant on other Evos?

 

I searched, Most with that problem are running mbc. Can you manually move the rod for the wastegate,? Mine seems kinda stiff.

 

I tried moving my own wastegate arm/rod when i was installing a o2 housing outlet. Its pretty stiff.

The overboost code means exactly that, your ecm has detected higher than "normal" level of boost running. Maybe your wastegate is sticky mine had some rust becuase of the heat so i put some anti stick , its like a powdered nickel coat in liquid form, on it and it seems to move a little better.