Guys i notice that when i am in third gear or second gear that when i am on the acclerator and i reach 4000 rpm my boost drops back down to zero, and if i want the 10 pounds it takes its time to get to 10 like its struggling but slowly makes it to 10 pounds by redline, is that how its supposed to be? my main point here is that i notice that once i hit the acclerator from 4000 rpm the boost takes its time to get to 10 pounds it feels like its struggling to get to 10 pounds, shouldnt come right to 10 right away when accelerating? sometimes i wont get boost once i punch it from 4000 to redline!!!! i notice this sluggish boost to 10 pounds when i punch it at 4000 rpm and unwards, below 4000 rpm the boost hits 10 fast, what could this be or is it normal? i just replaced both my couplings with silicone between the y-pipe and cross over tube and to the intercooler, also these are rebuilt turbos with only 5k on them.

 

I'm not totally sure here, but it sounds like your secondary turbo isn't working correctly. It could be the precontrol line and that your second turbo isn't pre-spooling, and that is what's taking it so long to get to 10psi boost. but even still, it shouldn't take 'that' long to reach 10psi. I'd check the precontrol line first and make sure it's not malfunctioning or the actuators.

 

well it actually doesnt get to 10 by redline it get there alot earlier but it doesnt hit 10 right away it goes up slowly going thorough 5,6,7,8,9 and then 10, shouldnt it get to 10 right away? this again happens from punching it from 4000rpm unwards, i believe the second turbo is responible for this!!

 

I have heard and experienced this issue before. It seems to be related to the turbo control system getting confused, but it is perhaps worsened by a worn or leaky component (check valve or hose). Unfortunately I don't know what parts to check.

-Max

 

I agree