7 PSI but no boost leaks

[bryce]

So i put all new intercooler piping on today and came to the conclusion that i was still only running 7 psi. I thought that maybe i had a leak in my intake or something, but my vaccum read a perfect 19-20hg of vaccum at idle. So when i went for a ride i was boosting at 7 and then all of a sudden it shoots up to 14-15. After that my boost went solid and turbo spooled as fast and as strong as it ever has. So i cruised around, thinking why this happened. Then it hit me i went and poped the hood and seen that the line came off the nipple goin to the wastegate off the j pipe. So then i figured out that my wastegate wasnt really hooked up. So could my wastegate or bcs just be getting old and not letting me do 12psi. I have a mbc to go in but im wating for some feedback, Do you guys think that would get me running solid 12-14 psi, Any input will help.

 

[madmike]

I am betting the housing for the waste gate is cracked wide open common problem when you get some miles on it. When you get time, pull the turbo off and inspect the whole housing and manifold for cracks and missing pieces...

 

[wret]

No, the wastegate is working fine. Your BCS is not. Replace it or use an MBC.

 

[bryce]

So if i put my boost controller in everything will be fine, and i will have solid boost?

 

[CanadianTSi]

So if i put my boost controller in everything will be fine, and i will have solid boost?

Yes.

 

[bryce]

So i threw the boost controller in and now im gettin normal boost again. The only problem im having is with my spark i think. I just wanted to double check with you guys and make sure this makes sense. When i floor it i get about 14 and sometimes it spikes, the only problem is that sometimes it will make and the exact same feeling the rev limiter makes, and makes that EXACT same sound. Do you guys think that a set of good plugs and wires would fix that. Or do you not think its ignition related

 

[oldman]

Which MBC and where are you tapping for pressure source?

BTW Just because you're pulling -20 inHG doesn't mean you have no boost leaks, it simply means there are probably no leaks after the TB plate, you still should run a boost leak test to check for pre-TB leaks. Type of mbc, routing of the mbc and boost leaks can all contribute to inconsistant boost level/boost spike.

 

[bryce]

Im not sure what kind of boost controller it is, It came with my brothers turbo kit for his Ecotec and he jus upgraded to ebc. I have it tapped into the wastegate pressure line that comes off the j pipe

 

[oldman]

Im not sure what kind of boost controller it is, It came with my brothers turbo kit for his Ecotec and he jus upgraded to ebc. I have it tapped into the wastegate pressure line that comes off the j pipe

Tapping the J-pipe is fine just make sure you leave the BOV line alone. Take apart the MBC and see if there it contains ball and spring or just a bleeder valve. Bleeder type valves (like the stock bcs) are known to cause boost spike, if indeed you have a bleeder type valve, you should get yourself a solid ball/spring type mbc for solid boost control. Don't forget about that boost leak test, you would have to be the luckiest or a very experienced IC pipe installer to have absolutely no leaks after a new install.