MBC didnt pass boost leak check. why

[alexg1323]

Ive got a hallman manual boost controller and on the outlet nipple to the wastgate as some might know it has a little barb hole that goes inside it. Well checking my pipes up to 10psi that thing is blowing out air. Is it supposed to do that? If so is there a boost controller more suited for our MAF operated cars.

 

[99gst_racer]

Are you trying to say that everytime you boost leak test your car, that your boost controller leaks air?? Is it from a vac line or from the controller itself?? You might just need a new controller....

 

[KRAZYKOREAN]

Ive got a hallman manual boost controller and on the outlet nipple to the wastgate as some might know it has a little barb hole that goes inside it. Well checking my pipes up to 10psi that thing is blowing out air. Is it supposed to do that? If so is there a boost controller more suited for our MAF operated cars.

yes that hole is there for a reason. But I will let you search why thats there. When you do a boost leak test either plug the hole with a tooth pick or something or just take off the mbc and run a longer vacumm line so your not using the mbc so you can boost leak test you shizznit.

 

[Dan7040]

Yes MBCs will. Most MBC's will have a bleeder valve built into them. This help reduces any boost spike by allowing the vacuum hose connected to the wastegate to be filled with some pressure, but not enough to open the WG. This effectively reduces the time it takes to open the WG once your preset boost is reached.

BTW I just kink my MBC's vacuum line and ziptie it when I do any leak tests

 

[alexg1323]

yea i mean i agree why its there, otherwise the wastegate would be stuck open on shifts and right after WOT. BUt regardless its spraying out alot of air? So thats a boost leak of metered air?