Vacuum/Boost Gauge Install Trouble

[Americanitemare1]

Hey guys, I’m having trouble getting any reading on my vacuum/boost gauge. The car is an 87 GN. The gauge is brand new and the car did not have an aftermarket gauge on it previously.

I T’d in from the hard metal line from the TB vacuum (2nd line that I’m pointing at in the pic) and the vacuum like coming off the MAP. The last line is connected to the gauge itself. All of the lines fit correctly to the T and are zip tied around them to stay tight.

I’ve sprayed around to check for obvious vacuum leaks and haven’t found anything. I assume I’m missing something obvious. I had tried this first with an old aftermarket gauge and it didn’t show a reading. Thinking it was the gauge, I bought a new one with the same result. Any help would be appreciated, thank you.

 

[blackazz]

I tapped into my Map sensor on the passenger side fender.put a tee there an try again.

 

[1986 Buick GX1]

I tapped into my Map sensor on the passenger side fender.put a tee there an try again.

It looks like that’s what he did, but his tee is next to the ign module/ coil pack.

 

[outatime86]

I know it sounds elementary but you can check to see if there is any blockage from the vacuum block going into the throttle body. Then also check the hard line itself see if you can remove it and blow air through it.

Goodluck, keep us posted.

 

[Americanitemare1]

I know it sounds elementary but you can check to see if there is any blockage from the vacuum block going into the throttle body. Then also check the hard line itself see if you can remove it and blow air through it.

Goodluck, keep us posted.

Just checked it and it’s definitely pulling vacuum. I took the line off the back of the gauge as well and placed my finger over the line. I can feel it pulling vacuum. I’m wondering if I didn’t use a proper fitting at the gauge itself. I wouldn’t have to do anything to a brand new gauge, right? It’s an Autometer 4301.

 

[TTA308]

I’m wondering if I didn’t use a proper fitting at the gauge itself.

Bingo