What are you guys seeing for vacuum at idle on your turbo engines? I have a MP70 on a 5.3 and it doesn't read less than zero on the boost/vacuum gauge at any time. This is my first turbo vehicle, I was under the impression they still made vacuum at low/idle rpm. The boost portion of the gauge works, just no vacuum. Thanks.

The gauge is connected to the PS port behind the throttle body.

 

Think mines around 14 vac at idle. 5.3 with m70 as well

 

Sure the line hasnt collasped with vacuum?

I had that problem with some cheap clear tubing.. it would only read about 1psi vacuum.. but would read boost just fine

 

Are you talking about the port on the TB that the valve cover was connected to, or the port about 2/3 of the way back on the intake manifold?

 

What are you calling the PS port?
Is it a larger 3/8" port, or the port on side of the intake manifold on about number 6 cyl runner?

 

im a slow typer

 

Ya the one the valve cover was connected to, it's still behind the throttle blade so should still work?

 

No, it isn't it turns in the TB and is in front of the tb blade. You need to connect your gauge to the port on the side of the intake manifold or the brake booster port.

 

Good to know, thanks man