Whats goin on guys, so here is my situation. My car runs strong, drives smooth. I thought that it was just my boost gauge, so i switched it with another, but none of my gauges are reading vaccuum.... is that even possible? I mean my idle surges up and down. (have a boost tester coming in today to find the leak) But could that leak take away from all my vaccuum? ive never seen something like this before. Thought i would throw it your way, any imput appreciated, Thanks guys...

P.S. Its a fresh large streetport 10th ann. if that helps, No other serious mods yet. Thanks again!

 

So you seem to be connected to a nipple that isn't vacuuum. Move to a nipple that has vacuum.

 

Did you connect it on one of the nipples between the TB and the intake? If so, thats your problem, its an atmospherique nipple.

 

thanks guys, ill double check that... That would really cause it to have absolutely 0 vaccuum huh?

 

if your car actually had 0 vacuum it would never idle.

 

Well i mean it couldnt be the guages. and it reads the boost, (hardly boost it because of fresh rebuild) but i do to like 2psi to make sure it worked. Its just wierd, there is no vacuum reading at all. But i will try what you guys said after work

 

It's not weird if you connected the gauge to a nipple that leads to a place prior to the throttle plates. On a USA turbo engine there are four nipples on the aft side of the engine. One above the other. Only one is vacuum. That would be the very bottom nipple.

 

my 88 has 3 on the back, but the bottom one is vac. I think it depends on production year?

 

well i have a 88 so that will help , thanks

 

"Aft" side of the engine, I like it. I had this problem, it was on the wrong nipple. OP- It does show vacuum when the throttle plates are open though, right?

 

doesnt show vacuum what so ever lol, but i get out in a hour or so, and ill check the nipples.. thanks guys

 

do you check what nipple is the one that have vacuum? I have the same problem with my boost gauge.

 

Only the bottom one whether you have three or four nipples back there.

 

that would be the number 4. There is a good place to connect the vacuum line for the boost gauge, Blow off valve, wastegate and MAP sensor?

 

^ I have my boost gauge tee'd into #4 in the pic, which is also going to my thermovalve. I use the bottom nipple on the front of the engine for my GM MAP sensor.

So in a stock car, what does number "3" go to on the 87 engines? #1 is injector air bleeds, #2 is oil injector air bleeds, #4 is water thermovalve on the TB on my 88

 

thanks guys, Hailers for the picture. worked perfectly , just hooked up to the wrong nipple. Took 30 seconds to fix, i appreciate it .

Dustin

 

I also connect my MAP Sensor and the boost gauge to the bottom nipple on the front of the engine. In the bottom one on the rear I get 0 vacuum, so I moved to the front.

I have a question, were you guys connect the vacuum fitting from the wastegate and the blow off valve to an engine vacuum source?