Boost controller going crazy after raising boost

[KadieTSi]

So my boost controller is acting very strange.


My wastegate spring is set at 10psi and I've had my boost at 12psi for a couple months now. Decided to go to 15 but the slightest turn and the first time it only went to 10psi as if running on spring.

I raised it more, about one more turn, and it boosted to 10 again. Raised again and it boosted to 22psi. Turned down one, boosted to 10psi. Turned up one, boosted 25psi. Turned it up once again, went to 26psi. Turned it down once, went to 25psi.

So I turned it down 3 times and it was boosting at 26psi again!

It's driving me nuts.

I just disconnected it for now and ran a vacuum line in place and am running off my 10psi spring.

I'm tempted to just run springs...
It's just strange how the MBC is brand new and worked perfect going from 10-12.

When I first put it on I did one turn and it took me to 11psi, one more took me to 12psi.

I'm wanting to run 15psi.

My car is easily ready for 25+psi but I'd rather slowly go up rather than jump to what my build is and then get bored and have to spend more money on something expensive to go faster. Right now it's built and all I have to do is keep raising the boost until I finally end up at the limit of my motor.

Thanks for any help

 

[GST4g63T]

What kind and brand of boost controller is it?

 

[KadieTSi]

It's a Hallman - brand new purchased around 3 months ago and only on the car for the last month and a half or so.

 

[GST4g63T]

Are you positive that you have it installed correctly? I'm not sure as to what would cause this.

 

[LiquidX]

How do you have your vacuum lines routed and what are the lines connected to?

 

[KadieTSi]

I have it connected to the compressor housing of my turbo, then a vacuum line from it T'd into the vacuum line from my bov that goes to the nipple on my intake manifold.

 

[LiquidX]

It sounds like you have too much hooked up. First off you do not T into the BOV line. Next, if you have a nipple on the compressor housing, that's the only thing you use. Compressor housing --->MBC inlet////MBC outlet---->wastegate/actuator nipple.

 

[KadieTSi]

Awesome that fixed it!

I went by the VFAQ for 2g for installation because I figured it'd be the same.

Thanks!

 

[kilo4]

You can do an operatiional check of the MBC off the car.
1. Remove the MBC with hoses
2. Connect the hose to an air compressor (manifold side)
- a hand held blow gun with hose barb fitting works great
-(optional) "T" off a boost gauge between the gun & mbc
3. Leave the hose that connects to the waste gate open to atmosphere
4. Regulate your compressor pressure to simulate boost pressure
- listen for a smooth mbc cracking pressure (a good mbc will not flutter)
- you can also dunk the mbc in a bucket of water to leak check
**when your done, you can leave it to a desired boost setting.