Boost Question


New member
Hello everyone.

I'm new to this forum and wanted to reach out for some info.

I have a stock 2020 STI.

Lately, my boost doesn't go past 10psi even in sharp sport mode.

It's like it's stuck in intelligent mode.

To fix this, I would then reset the ECU by disconnecting the negative terminal on the battery for a few minutes and then reconnect.

After doing this, then it's back to normal, but this would happen over and over.

Has anybody else had this issue?

Thank you.


Track Monkey
Do you have a code reader and/or getting a CEL?

If it's a 2020 & stock, take it to the dealer with the issue.


On a quest of STi erudition!
First and foremost, welcome to IGOTASTI!

You're going to love it here!!

So, you reset the ECU and allow it to relearn the parameters.

Then when you WOT in Sport or Sport #, you achieve peak boost.

However, after some time, the peak is 10 PSI?

What occurred before this issue showing up?

Curious as to what your dealer will say about this.


New member
That is correct.

After some time, I noticed it doesn’t go past 8-10 psi again.

I drive it regularly, not even aggressive.

It doesn’t happen too often but enough to become annoying.