Losing boost after hitting full boost...

[siks13sr]

i got my boost gauge the other day after i orderd some new gaskets for my manifold and turbo... after i replaced the gaskets i was watching my boost gauge an i got around 6 lbs, then as im on the throttle it just starts dropin...

I have a manual boost controller but we took it off not too long after we put it on bc it did the same thing at stock boost as it did at 10 lbs .

Boost Leak? or what

[jhillj1]

hey mn i o almost the same problem but when hit like 6 or 7 pounds it drops and cant go above like 5000 rpms i have to shift out the gear if u get any ideas let me know

[Hijacker]

when my turbo started to go bad, it would build to max boost and then drop off a few pounds slowly. I would pull the intake piping and check for shaft play.

Also, don't rule out boost leak. If you can pressurize the intake system, you can find the leak. I have a little metal cap I can insert into the intake piping where the MAF normally goes. it has an air fitting that allows me to hook up a pressure regulator, so I can pump controlled air into it and find out at what boost levels it leaks. (most major leaks become evident at 5 psi)

[siks13sr]

hey jhill, i think we actually have the same problem here... i cant rev past 5500 sometimes 6000 also... and that would lead us to what tenkawa said, either shaft play or a boost leak. i checked my turbo for shaft play an it had very slight shat play so that may be my problem then. Thanks guys