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Boost Needle shakes under vacuum

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Old 05-29-2012 | 05:34 PM
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Default Boost Needle shakes under vacuum

My boost needle has been recently shakes a little bit,only in vacuum..when im in boost its fine,i have a autometer utlra lite one...i read that it good be a leak,someplace...its a brand new hose,i have it running,to my vacuum block...i tryed different gauges,all do the same...

any suggestions.....
Old 05-29-2012 | 05:40 PM
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What is your vac source? Off or near the vsv perhaps?
Old 05-29-2012 | 07:01 PM
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is it a electronic or mech? if it's electronic are you using the same sensor? could be a bad sensor.
Old 05-29-2012 | 09:06 PM
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Originally Posted by crush02342002
What is your vac source? Off or near the vsv perhaps?

throttle body
Old 05-29-2012 | 09:07 PM
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Originally Posted by Syldrin
is it a electronic or mech? if it's electronic are you using the same sensor? could be a bad sensor.
mechanical
Old 05-29-2012 | 09:53 PM
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so you tapped inbetween the throttle body and the vsv?

if you have a spare t-fitting try tapping off the brake booster or if you have a vac line to your turbo comp housing try tapping into that and see if readings calm down a bit.
Old 05-29-2012 | 10:05 PM
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Mines does the same.

-Sent From DarkSide Sense 3.5 -
Old 05-30-2012 | 01:34 AM
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Originally Posted by crush02342002
so you tapped inbetween the throttle body and the vsv?

if you have a spare t-fitting try tapping off the brake booster or if you have a vac line to your turbo comp housing try tapping into that and see if readings calm down a bit.

maybe ill try that,to the brake booster......i had a glowshift boost gauge,i borrowed from my buddy,just to check,mechanical,that thing was even worse,im hoping its not my boost gauge,or a leak...
Old 05-30-2012 | 01:35 AM
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Originally Posted by scion86
Mines does the same.

-Sent From DarkSide Sense 3.5 -

what gauge do you have..............i just find it annoying, lol
Old 05-30-2012 | 01:59 AM
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Same as yours and I hooked it up the same way
https://www.scionlife.com/forums/tc-tech-diy-1818/gauge-install-autometer-27143/

that's how I did it and it's all over the place I thought it was normal and some times it goes to zero and just stays there when I'm at like 2500 rpm I got the supercharger tho idk if there's a difference

-Sent From DarkSide Sense 3.5 -

Last edited by scion86; 05-30-2012 at 02:57 AM.
Old 05-30-2012 | 02:38 AM
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Originally Posted by scion86
Same as yours and I hooked it up the same way
https://www.scionlife.com/forums/showthread.php?t=27143

that's how I did it and it's all over the place I thought it was normal and some times it goes to zero and just stays there when I'm at like 2500 rpm and my bov kicks in lol.and I'm Not in wot eaither I got the supercharger tho idk if there's a difference

-Sent From DarkSide Sense 3.5 -

interesting,mine starts to shakes a bit only at idle,but as the car is warming up,needle seems to move smoothly,and not bouncing around,holds steady when im in boost,just the idle thing,i check all connections....just weird..i googled it,and alot of results,came up and seems to be common,why,idk why lol
Old 05-30-2012 | 02:56 AM
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Yea once I'm in boost it's steady and in idle its all over the place. And when I drive but once I hit.a lil over 2500 rpms it goes to zero and stays there. Till get into boost idk it's my first boost gauge and I thought it was normal if the vac bounced around. Lol.

-Sent From DarkSide Sense 3.5 -
Old 05-31-2012 | 03:01 AM
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Mine shakes too, It is a autometer as well I have a vac block tapped off the tb. I hate that gauge. I am going with something that has a barb fitting rather than the little mini hard hose.
Old 06-01-2012 | 06:34 PM
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up date...went to my local hardware store and picked up a barb fitting for the gauge,installed it,and the needle moves alot smoother,and no more shaking,at least from what my own 2 eyes can see lol....
Old 06-01-2012 | 09:03 PM
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So you got rid of the crappy mini hardline and went with a barb and vac line? What size was the barb if you don't mind.
Old 06-02-2012 | 02:26 AM
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Originally Posted by headlessmunky
So you got rid of the crappy mini hardline and went with a barb and vac line? What size was the barb if you don't mind.
yes,got rid of hardline,never liked it,to begin with,i brought the gauge with me,and they match it up with the correct barb fitting,that uses 1/8 vacuum hose...
Old 06-02-2012 | 03:44 AM
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I actually have an extra one from my Ptuning Vac block! I will be installing the rubber vac hose when I get my gauge cups in.
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