OVER BOOSTING PLEASE HELP!

[turbolegacy93]

I fixed a hole in my boost controler and now im hitting like 15psi and no fuel cut? I Have 3in straight pipe turbo back and a catless uppipe. i mess with the controler and nothing changes. what should i do?

[Legacy777]

Are you running the stock boost controller (wastegate solenoid)? How do you have the hoses hooked up to the wastegate solenoid?

[tsbpenguin]

Where exactly on the boost controller was this hole that you fixed? What did you do to fix it?

[devilzdriver]

I have the same problem man, but my leggy came with a custom intake so my 3rd port on my BCS can't connect to the intake so i plugged it. but i still get spike. I have heard many things that it can be. But nothing seems to fix it.

[alexandermf]

^just cuz you have a custom intake doesn't mean u can't plumb a hose back into it... I have my 3rd port being tee'd back into my intake

[devilzdriver]

^just cuz you have a custom intake doesn't mean u can't plumb a hose back into it... I have my 3rd port being tee'd back into my intake

I honnestly never even thought of that

[Legacy777]

That third port must be vented either back into the intake or to atmosphere. You should be able to tee it back into the intake (pre turbo). It must be pre turbo.

[devilzdriver]

That third port must be vented either back into the intake or to atmosphere. You should be able to tee it back into the intake (pre turbo). It must be pre turbo.

Ok did that still got boost spike, i don't mean to thread jack....

[Legacy777]

Do your vacuum lines more or less look like what's in the diagram?

http://surrealmirage.com/vrg3/vacuum/ej22t_vacuum.png

[devilzdriver]

more or less, the only thing is my MBC thats in the connection to the wastegate. I assume i should just take it out?

[alexandermf]

Leave it in and keep it connected so the ecu doesn't freak out, just cap the ports

[Legacy777]

Ok....let's try and clarify things. You mentioned something about a third port and not venting that back into the intake. However, if you have a MBC, then it doesn't matter, so which do you have currently controlling your boost? MBC or the stock wastegate?

If it's the MBC, you should keep the electrical connector for the stock wastegate solenoid plugged in so the ECU is happy. None of the vacuum/boost ports need to be hooked to anything, just plug them.

On your MBC, the line coming from the turbo's compressor outlet should go into the MBC, and then the outlet from the MBC should go into the wastegate actuator.

If this is how you have it setup and you are still over boosting I would suspect you may have boost creep or just need to turn the boost down on the MBC. When do you overboost? Does it occur only in higher gears or does it occur in lower gears as well?

[devilzdriver]

Ok....let's try and clarify things. You mentioned something about a third port and not venting that back into the intake. However, if you have a MBC, then it doesn't matter, so which do you have currently controlling your boost? MBC or the stock wastegate?

If it's the MBC, you should keep the electrical connector for the stock wastegate solenoid plugged in so the ECU is happy. None of the vacuum/boost ports need to be hooked to anything, just plug them.

On your MBC, the line coming from the turbo's compressor outlet should go into the MBC, and then the outlet from the MBC should go into the wastegate actuator.

If this is how you have it setup and you are still over boosting I would suspect you may have boost creep or just need to turn the boost down on the MBC. When do you overboost? Does it occur only in higher gears or does it occur in lower gears as well?

See, i am totally new to turbos, heck even fuel injection lol. I was looking at my car, and the boost control setup it has, or confusion of.... The MBC is connected to the turbo housing and then to the center port in the stock solenoid. So now that i know the MBC goes from the wastegate to the compressor housing im gunna do that, and then plug the solenoid. Hopefully that fixs it

[free5ty1e]

Yep that oughta do it! And if not (still overboosting?), try reversing the lines through the MBC. (they can be hooked up backwards and the turbo boost just never makes it to the wastegate as it's pressing the wrong way)

Turbo -> MBC -> wastegate:
That's all there is to it