Now I know there have been other posts on this and I have done a search. Even though I've read some other posts I havent seen a definative anwser to the problem.

Here goes, I have an 05 evo 8 mods in signature. The cars has been running fine up until a couple weeks ago. I used to be able to turn the BC on high or low and it would hold that boost regardless of how fast or slow I was going.

Now if the BC is in high or low the boost will build up normally and hold but only until about 5000-5500 rpms. After that it wants to keep going up and I dont really have the fuel system or a built motor to see how high it will go.

I have replaced the vaccum lines, tested the solenoid for function, and backed off the wga. These "quick fixes" have done nothing if anyone can help I would really appreciate it.

Thanks,
Jesse

 

mybe a fresh tune and a new wastegate will solve it

 

+1

 

Thanks for the suggestions.

 

boost leak test? check the upper intercooler hose by your throttle body that's where I had my problem. I would get good boost till 3600 and then it would slowly taper off meaning I was losing power across the powerband