Ive been having what seemed to be major misfires while WOT, but my engine threw a code that says its the wastegate system. When I bought the car he had just replaced the stock wastegate with a new one (idk what brand) since the car is running 24psi. Does anyone have any recommendations on what I should look for when I dive in tomorrow? I always thought the wastegates were pretty simple without much that could break, except the spring I guess.
If a new one is needed, what do you guys recommend?
(It's an 05 evo VIII)
Also, I haven't had a retune since I bought it, but the only thing Ive done to it is i installed an o2 dump.

 

Is it ecu controlled waste gate or do you have a manual/electronic boost controller? I assume its all stock and ecu controlled, first I would be looking at the misfire problem since thats way more important and can be related. Hows the spark plugs look? whens the last time they were changed?

 

I have a manual boost controller, and the issue happened before a changed the plugs, and after. They didn't look bad when I changed them. So I don't think it's them.

 

Chase...

Did you gap the plugs properly? Check your gap. Pull them out now and see what they read. See if there is any issue with them as well.

Since you installed the O2 dump and opened up the housing by doing so the only thing you might see is boost creep.

Odds are you have a Forge or FP wastegate (pretty popular) options. Let me know and we can take a look.

 

Whats up ray!

Yeah they are gapped properly, i checked probably a week ago by now.
I'm about 99% sure its a forge, at least that is what it looks like. I just find it hard to believe its already failing.

 

Maybe it's hitting fuel cut. A retune is advisable after the O2 dump install. Did you go from a stock O2 housing and stock WGA to the dump and the HD actuator?

It is possible that it was tuned for the stock WGA with little to no preload and now you are running a heavier actuator spring and less exhaust back pressure due to the O2 dump.

So, ECU is seeing a lot more air in a significantly lower engine RPM range. Another way of looking at it is that the car was tuned for a certain max volume of charge air. Now, with the changes that you made that max charge air volume is happening further to the left.

The car needs to be retuned first.

 

Would this be something I could see in a pull from his ECU in sections like wastegate duty cycle?

Or would the preload actually have to be adjusted on the wastegate spring itself?

 

This sounds like it could possibly be it. The previous owner installed the new wastegate, and that was after the tune the owner before him did. So this is likely. I will get it retuned and return with the results soon.

 

Any updates?