Why can't I boost higher than 9 psi?

[Silverbullet91]

Hey guys whats up. I was driving to work this morning and when I got to the freeway on ramp I noticed I wasn't making more that 9 pounds of boost. I have been running around at 12 psi. What gives? I've got the stock t25 on my redtop with a manual boost controller. I did a quick look over in the parking and couldn't find anything obvious. Even turned the boost controller up a little-didn't really make a difference. Other than that the car drives great, no hesistation, no smoke, no funny noises, etc. Anybody got any ideas on this?

[9240sx]

What kind of boost contoller is it?

[Silverbullet91]

Hey man, thanks for the response. I appreciate it.

Its a DNA manual boost controller. Like I said its been on there a couple of months @ 12 psi. It was even fine yesterday. Hope my turbo is not getting ready to die on me. $$$$$

[NIGHTfall_240sx]

weather can effect your boost levels.

i remember ona hot day i was boostin 12psi, and with the exact setting on my controller (34%) on a cold day i was hittin 15psi? (around there)

[jr_ss]

You could also have a vacuum/boost leak...

[Silverbullet91]

Your right nightfall; Weather can have a big effect on a manual boost controller. But I went from 12 pounds to 9. Overnight. Colder air is more dense and will often have you making more boost. And it wasn't exactly 100 degrees yesterday. Besides it was making the 12 psi in the summer heat so thats not the problem.

Also if I had a boost leak I would think the car would be sputtering and bucking and skipping all over the place. And if there was a vaccum leak say like to the wastegate actuator would it just want to stay closed and make more boost instead of less. I freakin out here man!

[bdrifta]

are you running a stock bov...because my car did the same thing...and i built a pressure tester for my system, and it was my bov, it leaked under boost, but not vac. I replaced the bov, and now its perfect.

[Silverbullet91]

No, I'm running a greddy type rs bov and greddy front mount. I was planning checking for boost leaks this weekend but I just got home from work and looked under the hood in the daylight and what do I find...the hose I used to recirculate my bov is covered with oil. No!! Time to take a look at the shaft play. Also, now I think I might be hearing some faint metal sounds just as the turbo is to starting to spool up under light throttle. I haven't even put 3,000 miles on this motor since the swap. I'm getting some beer...

[luv2spedup]

yep check for leaks and keep us posted

[Silverbullet91]

I'll keep this up to date, but it might be a while before I have something new to say. I'm having to work on my girlfriend's car this weekend (a whole other story) so my schedule is kinda full. I've just parked my car for the moment.