I was curious if anyone has any experience with these. I installed it a couple weeks ago when I installed the A/F gauge and everything else. Its not reading vacuum. It reads boost fine, but when I'm ideling it just reads zero instead of a vacuum. I have it "tee'd" into the boost hose line that comes off the cold side of the charge pipe, down by the intercooler. Did I put it in the wrong spot or something? Any help would be great. Thanks guys

 

Subscribed for more detail.

In the meantime...

I bought a digital gauge (not yet installed) that was described as a boost gauge, and the write-up read that "it also measures vacuum". The description on other digital boost gauges did not include that wording; I took it to mean that some digital boost gauges will additionally measure vacuum and some won't. Those that do, in my shopping experience, measure the vacuum in psi rather than inches of mercury, this from talking to the sales techs. Reading vacuum in psi is unfamiliar to me (kind of a downer). Kind of interesting that a mechanical gauge is easier to peg by using a different scale on the same face, but a digital gauge isn't (or can't be) converted by the chip/board- or perhaps there's more to it than this.

Clarification of this admittedly small item might help both the OP and myself, and maybe another reader or two.

 

I'm not trying to be a dick...but this is more of a question to e-mail AEM's tech support about. My guess is it's a boost only gauge and doesn't read vacuum. Cuz if it will read boost, then it should be reading vacuum too, it's not like vacuum only exists in one certain spot in ur charge piping setup.

 

Well I mean its got all the LEDs and everything and shows vacuum so I would assume it does. I was just checkin to see if maybe I hooked it up wrong or something. I'ma call AEM sometime tomorrow or maybe tuesday...

 

So I emailed them and this is what I got...

"Samuel,

Hello. If the gauge is reading boost fine, but not vacuum, I would suspect that you might have tapped reference source after some sort of check valve or 1-way valve.

Where do you currently have the sensor tapped? Is it in exactly the same location as stock?

You could manually test the gauge by getting some sort of Mighty-vac hand pump or something similar that can pull vacuum.

Thanks."

What I replied was that I "tee'd" into what I thought was a boost/vacuum line that is right after the boost sensor on the cold charge pipe right after the intercooler. Again...did I put it in the wrong spot or something?

 

Try teeing it into the line right off the intake manifold on the top center.

 

^^qft!!!

 

You have it installed in the wrong location.

If its in the cold side charge piping, its not going to read vacuum, only boost. It needs to be installed after the throttle body to read both vacuum and boost. There is no vacuum in the charge piping, only in the intake manifold, hence why you aren't showing any vacuum when the car is idling.

 

alrighty. Thanks for the info. I'll be setting that up this weekend. Thanks again for the help guys. Much appreciated. I'll post pics when its finished...

Can you guys "idiot-proof" it for me with this pic?

 

I can tell ya which one i used. See the engine oil dipstick? Now, right above that you see this little black box with 3 vacuum lines going to it? ok, to the right of that, there is a nice vacuum line that goes to a fitting that goes into your intake manifold. Right there is where you want to tap into.

 

Alright alright...Sounds simple enough. Now I know this is prolly redundant...but I just wanna make sure. I don't wanna keep cutting lines and putting them back together

 

yes

 

Nice...thank ya much

 

no problem

 

exactly where i tapped into. works perfectly.

good luck!