Boost Gauge reads at 0 PSI going 80 MPG

[Dsm 95 Tsi Awd]

Hi guys, need some advice. My boost gauge runs fines, its just when im going about 70 or 80 MPH, the boost will stay at 0-2 PSI. I know with my brothers car when he is going that fast, his says around -10. So when im going on the highway, im sucking up a lot of gas that i think could be prevented, any information will be helpful, thanks....

-Alex

 

[TooFastTooG]

Your boost isn't determined by how fast your going, I can floor it from a dead stop and be going 0-55 with 15 psi, but when someone is just cruising on the highway doing say 70 , it is normal for you to not be in boost with your foot lightly on the peddle.

Also, throttle position doesn't have to do with everything ether, the load on the engine plays a big parts as well.

 

[Dsm 95 Tsi Awd]

but to my understanding, i shouldnt even be pushing 0 PSI

 

[Staytuned]

Your right you should be pulling more vacuum than that while cruising (not while accelerating). Check all your vac lines and look for boost leaks.

 

[larsenracing]

Is it possable that you have low compression or something

 

[oldman]

What is your vacuum reading at idle?

 

[Dsm 95 Tsi Awd]

at idle, its reads -20- through -25, roughly around that....

 

[oldman]

Where did you tap the boost gauge line, the fps line or the fpr line? The only thing I can think of is that you tapped the fpr line and the fps is some how being activated causing the gauge to read zero. Just a wild guess though.

 

[Dsm 95 Tsi Awd]

i tapped into the the middle vaccuum hose on the throttle body. There is a specfic letter given to it, but i forgot, i just know its in the middle of the three.

 

[TooFastTooG]

This should help you point out where you are tapping the line, mine is tapped all the way to the right you can just see it.

 

[oldman]

I'm not familiar with a 2G throttle body and how the ports are interconnected but tap your boost gauge at the fps line and see if things change.

 

[Dsm 95 Tsi Awd]

This should help you point out where you are tapping the line, mine is tapped all the way to the right you can just see it.

yeah, i see where you tapped in, i was going to tap into there just because its the most accurate, but for some reason, i cant remember why i didnt. Someone had told me that going to the throttle body would be accurate, it would just give me the reading of it at that position at the throttle instead of where the intake and head meet. Thanks guys for all your help, ill try rehooking it up and see if that fixes it, if not, well..................i dont i guess, if you still got some ideas, ill keep that into some consideration.....

THANKS AGAIN GUYS

-alex

 

[talonTSIDriver]

You want to tap into the center vacuum line on the TB. vFaq says to tap into the Fuel Pressure Solenoid, otherwise the "P" outlet on the TB.