K so I boosted a 90 DA bout 2 weeks ago and the guy went ahead and put a MBC in the bitch on friday. Since then for some reason hes not going above 4 psi and the spring is 5psi. He said he was rocking 10 psi for a few hours after putting the MBC in and then it just wouldnt go above 4? He dissconected all the vaccum lines from the wastegate and still, wont build boost above 4psi. I swung by his place for about 10mins to check things out and everything looked fine but it was dark. Didnt have time ot pull off the DT and check to see if i might be stuck open. Ill check that tomorrow if I have time. Anyone else have any other ideas?

 

busted diaphragm??

 

mabey a charge pipe has a leak in it. dose it take longer to build the 4psi now?

 

+1

 

what turbo is it my ching chang, for bout a week wouldnt boost over 5psi, even with a block off plate one, then one day it started to work fine again,..

If not a ching chang, id say check your couplers

 

If it's not cast, It could be your mani. Check for cracks and make sure your turbo isn't hanging from the flang by one bolt...