ok so i just installed a brand new aem boost gauge on my 06 r53. its the type that has a sensor and a vacuum line goes into your source. my problem is just weird. the gauge works perfect in vacuum. shows correct vacuum until i go into boost. if i bash on my throttle and redline the car the gauge is showing like 6 psi of boost. now if i push my throttle slowly my gauge will show 13 psi and then jump back to 6 psi at like 5k rpm so i cant even see my 15psi on the gauge. its unusual. i tried to have all the correct size vacuum lines except the stock plastic line is still their.
basically my routing of my lines go like this. stock vacuum plastic is still connected from the manifold. then it t-s off into the fuel pressure regulator. then one line t-s off again going into my boost gauge sensor and my recirculation valve. the little port on the recirculation valve is blocked off. i did the recirculation mod.
the only two things i can think of is the oem plastic line is to skinny or my 12v source is not good. causing some sort of interferance. but it doesnt make sense cause the gauge works fine. i connected it to a green wire with yellow strip on the lock cylinder.

anyone have an idea why its getting this weird low reading at wot. oh and i have a 15% pulley. i used a obd reader and torque app and that showed me 15.5 psi of boost. my car is pulling so i know theirs no leak.

 

When you have your car off and turn the lights on does the gauge work the right color? When The Car is on does it show the right color? You may wired into the wrong wire or it is weak or a short (not all the way on)...another option is to look at your Ts...sounds like alot of T-s make sure they are connected correctly an in the right places. All else fails START OVER.

 

Also, I have the OB Sensor also and if you are reading good on the App then it is def your wiring going from your splice site to your gauge itself. Was the gauge brand new?

 

yes the gauge is brand new. maybe ill take the 12 volt source and connect it to another 12v source is my next step. all my ts have crimped bailing wire so i know nothing is leaking. maybe its the 12v source not being pure. what wire do i splice my 12v source in. can someone post a pic or just tell me where the wire is. the gauge doesnt show like it has low voltage it looks perfect. this is annoying cause i already took my intercooler off three times to check for anything. maybe ill just drill a hole in the manifold and tap in a nipple. all these ts are no good to have in the first place anyway. anyone have a vacuum block on their mini?

 

Doesn't sound like an electrical problem to me.
It seems more like something is causing a leak or loss of pressure during boost. Are you sure you have the gauge tap at a point directly into the manifold without any other hoses connected? I can't tell from your drawing but if some other engine control valve is tapped into the same point it could be opening up during hard acceleration.

 

Your hooked up to the wrong line. There's a little tube that connects to the bottom of the intake manifold (i think) the T goes there. Should be the first line in your drawing, not the second.

 

yea i have a feeling the recirculation valve is bleeding off somehow. i will put the line closest to the manifold. i just wish we had more ports on the manifold. is their any way the recirculation valve leaks air under hard acceleration through out the powerband? But like i said the car pulls and runs perfect so how can i have a leak? This valve could be the issue. thanks for the sugg. so far guys.

 

so i connected the T closer to the manifold like this. basically this is my routing.


the problem seems better now im seeing 11 psi of boost but like i said my ecu is showing about 14.5 \ 15 psi. is my valve leaking? if its leaking how can i get perfect boost. or maybe my ts are to small. im thinking about either buying a vacuum block. or ting off my brake booster.

 

^ he is correct just try that line

 

im gonna try to drilling a hole into my intake manifold and tapping a fitting in their. if your thinking about the metal shavings its easy ill just lube up the bit with grease and use a vacuum and nothing should fall in the manifold. i have tested it before and it works.

 

Why would you drill into Anything? Try these PDFs first...

Look here...

http://www.billswebspace.com/R53GaugeInstallation.htm

And here

http://www.mossmotors.com/graphics/p...ns/100-921.pdf

 

thanks for those links. maybe ill just put the vgs mod back to the way it should be and use one t not two i think thats why its showing less boost. by me switching closer it helped the gauge but not fully. dam vgs mod messed me up here lol.

 

You should be able to get to the right hose with some long pliers. I didn't have to remove my IC. I dunno about that Vgs mod... Seems like that would mess with the computer, and other stuff. Do you have a pulley or anything?

 

yes i have a pulley and i did get to the right port. the vgs mod didnt effect the computer at all i ran it a week before i installed the gauge. having two t's is the problem i think.

 

Double check everything, and yes you might as well undo the VGS mod while you're at it, really doesn't do that much with most setups so why not take it out of the equation. Make sure all your T's are not cracked or split from heat and that the line fitments are tight, esp. at the fuel regulator. Once you've checked all that I think I'd give AEM a call about trading you for a new sensor, just to make sure it's actually not your problem, they can actually be pretty delicate, I know my sensor gives me lower than normal readings when it's really cold out, so if just a temp. change can have an effect, who knows how easily they can be damaged, wouldn't hurt to rule it out anyway.

Oh, speaking of VGS mod, are you sure the line you pulled from the BPV is plugged and/or capped properly?