need help! boost leak but where?

[irjoshy]

first of my mods are:
2.5"downpipe
high flow cat
2.5" cat back

buschur MBC set at 9 psi(the lowest it goes)

act 2100

and a 1g bov
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my problem lies somewhere in the air system... but i can't find out what exactly it is... at first i thought my stock bov was just leaking so i replaced it with a 1g bov.... but i used the gasket that came with it(maybe thats the problem)? i tightened all of my hoses including all of the intercooler pipes...

what happens is that when i go WOT the car sputters makes a loud whoosh and black smoke comes out of the exhaust...

none of this happend untill i put on my manual boost controller.....

help would be greatly appreciated!!!

thanks guys

-josh

 

[temfate]

Have you built a boost leak tester? Also, do you have a boost guage and know for a fact what boost pressure you're hitting? Black smoke could very well be running very rich (air leaking). Is the BOV stuck open maybe? Are you venting to atmosphere? This could really be a lot of things, that's why a boost leak tester is a good idea.

Also, where is your MBC connected? Is the high pressure source connected opposing the set screw? Or vice versa?

 

[irjoshy]

well.. i do have a boost guage. it reads 15 psi at wot when it starts to stutter

and i dunno about how the boost controller is connected.. i had buschur put it on when i had them install my clutch...

how can you tell if the bov is stuck open?

 

[temfate]

The easiest way to tell if it's open would be to build that boost leak tester. Basically you pressurize the turbo, and listen for leaks... The BOV should not leak any air out...