PearlWhiteX

My Evox has an overboosting problem that I've ran many test on but still can't figure out so I am hoping one of you might have an answer. Car is stock, 2008 with 94k miles. Temperature outside is about 40 degrees F. Already did all the fuel test and came up with no issues.

Checked for leaks. Came up none
Wastegate and blow off are working perfectly.
Replaced MAP sensor and MAF
Replaced the black boost solenoid (brown seems to be working). Even tested them with hooking up power to them and blowing air through them, worked perfectly.
After all this the problem still exist.

They only way we got the problem to go away is disconnecting the electric to both solenoids and boost held in 2nd gear at WOT at 15psi which is what should happen, connected them back and overboosting again.
According to EvoScan I am producing 17psi yet my boost gauge which is hooked to the intake manifold is getting 20+ maxing out around 25. The main symptom is that at full boost the car chokes and traction control shuts off.

I feel that what ever the ECU uses to sense boost is malfunctioning but I cannot figure out what, any ideas?

awdxftw

iTrader: (9)

I know it may seem a little silly but check the vacuum lines, also check where you hooked your boost gauge too. I had a super small leak in my t fitting and had the same thing happen.

Luke Glass

put a manual boost controller on it!! should fix everything

icemann

Manual boost controller should always be caused because it takes the electrical aspects out and allows you to control how much boost you want and a good tuner will also set it right for you .... if you need to know a few a good options on them man let me know..

Rmr298

iTrader: (1)

It sounds like an electrical problem if the BCS is ok.

icemann

Yah you don't have a manual boost controller so you have nothin to regulate boost a boost Guage will just tell you what the boost level is.. you really need to have a manual boost give cost tops 300 bucks and you won't have to much worry..

icemann

Yah you don't have a manual boost controller so you have nothin to regulate boost a boost Guage will just tell you what the boost level is.. you really need to have a manual boost give cost tops 300 bucks and you won't have to much worry.. also the maps you could be getting could be bad as well ..

venom225

have you recently messed with your ground connections? When I had my STi it had sensor related issues after one of many rebuilds, turns out I missed a ground after I yanked the motor out to rebuild it. The difference is I had several issues not just one issue. But im not as familiar with the EVo scheme. maybe worth a look!