I lived in GA and moved back home to Minnesota. Drove my car (first mistake) but car drove fine. As i got here everthing was fine until i found a crack in my manifold. Long story short i got a whole new manifold in now and evertyhing else is the same but i went from 20in/hg and it has slowly gone down to 4!!! Ive replaces all vaccuum lines also me and a friend who is pretty well mechanicly smart have looked and are a little in the dark. Anyone know anything that can help me. Even the smallest susgestion will help please. I tend to look over stuff thinking its always the worst. I have:


B16a
garrett t3/to4e 60 trim turbo
Tial 38 mm blue to wastegate
walbro 255 lph fuel pump
dsm 450cc injectors
tuned with uberdata
3in dp
3in exhaust

a little bit of info to give you a little bit to go off of. Would love the help. Car is driving me crazy i cant boost

 

the car is showing no signs of vacuum leaks anymore?

 

check your valves

 

No i cant seem to find any vaccuum leaks. I dont hear and "sucking" sounds. The car idles up and down but it is very slow when doing so. about 2 seconds in between when it goes up and down. Ranging around 1k to 2k. Im not throwing any codes or anything. It just seems weird that the car was running fine then all the sudden it started to slowly loose pressure from 20 to 4in.hg and stay there without moving anymore. Could there be a leak somewhere im missing?

 

yup, try pulling out the PCV valve, and plugging the IM port, i bet it will go back up to 20hg, I BET ON THIS>

 

A drop that deep on intake vacuum would mean a major intake leak and the engine should be reving like crazy. Since that's not the case, either the valve timing is off, the test point isn't giving you the true manifold pressure, or the gauge is whack, or the hose to the gauge is kinked and/or leaking.