Boost Gauge Reads Constant Vacuum

[skreetracer87]

I just installed an autometer boost gauge in my tsi and it read vacuum 90% of the time. Is this right? When im really steppin on it the boost runs up to bout 11-12 but as soon as i let off it jumps back down to bout 10-15 in vacuum. is this normal or what. I printed instructions off of roadraceengineering.com which tells you to put a tee in the hose that runs from the intake to the solenoid. Is this the accurate one or not? Im thinkin from what ive read the "p" hose on the throttle bottle is the easy but not so accurate one. Any help appreciated. thanks

 

[blackGSX2g]

When your car is sitting at idle or you are just lightly cruising, everything is in vacuum. As soon as you hit it, the gauge should jump out of vacuum as you start to build boost.

As for your T, between the intake manifold and the FPR solonoid is fine.

 

[ICGerms]

What does the gauge read when the car is turned off?

 

[totaleclipse_05]

Boost/Vacuum gauges, when engine is not running, reads "0".

 

[stirpicult]

it probably reads vacuum 90% of the time because you aren't in boost 90% of the time. this sounds completely normal. you should only be building boost when you are 'really on it.' when i am driving around normal i might not reach boost ever.

 

[92GSXBaltimore]

your next mod needs to be this
Super Killer Mod, Son Son!!!!

 

[ICGerms]

Boost/Vacuum gauges, when engine is not running, reads "0".

Then you should be fine. Like everyone else is saying, you're in vacuum 90% of the time because you're only boosting 10% of the time.

 

[totaleclipse_05]

Then you should be fine. Like everyone else is saying, you're in vacuum 90% of the time because you're only boosting 10% of the time.

Exactly, turbos build boost by using exhaust gases to spin the turbine. If you aren't on it much, AKA flooring it or in high rpms, then the boost won't build up a lot because the gases aren't flowing through the turbo as much or as fast.

 

[toutsuu]

Just to repeat what pretty much everyone else is saying, I installed an aftermarket gauge too and it behaves the same way which is perfectly normal. Perhaps you were thrown off by the stock gauge because it only goes down to -7 when the vacumm is actually more than that, just another way the stock gauge is inaccurate.

 

[VegasTSI]

Just installed a autometer boost gauge tonight, and if you arent on the gas to where you can hear the spool, your in vacum, 100% nohing wrong with that.

I found the CAI I bought off of ebay with the raliart filter lets me hear everything the turbo is doing, and I can compare that to the boost gauge to kind of troubleshoot issues. Very good investment, only cost me like $55 after shipping

 

[coving21]

Everyone is right but it very important to understand how a turbo car works. Like everyone is saying you shouldn't be under boost unless you are trying to go fast or at least get up to 60 quickly. You should read some of the forums they helped me to understand exactly how a turbo works.

 

[ZachM31]

howstuffworks is a good site for beginner stuff... you can go to garret.com and they have liek turbos 101, which is general information for turbo chargers, 3 levels too i believe, or else find books, Maximum Boost by Corky Bell is an excellent book for turbochargers, i learned more than i thought from it... or else ask anyone on the site, i'd say 90%+ of us know how a turbo works..

 

[AmpleEclipse]

You might want to check for ANY crimps and/or leaks in your autometer boost/vac-tube-wire-thing. You should be around 17-20 in vacuum at idle. If thats all good then you may want to run a compression test on your head to check for a weak cylinder!

 

[tstkl]

i love how someone posted that a mechanical boost gauge is at 0 when the car is off, in response to someone asking, "whats it read when the car is off"

when really he asked that to see if his boost gauge was defective, like if it sits at -4 when the car is off, notice how that guys sig was right under his post, that means that was the first time he posted in this thread, let the person with the problem answer the question..... what does it read when the car is off?