I have a question regaurding my boost gauge on my 09 SS/TC. It it normal at idle to have 20 hg of manifold vaccum?

 

Mine idles around that i believe or when im coasting not giving it any gas

 

RPD doesn't show vacuum!

 

Yeah, that does seem odd they would leave that out with all the other available parameters.

 

Wow. ok! so it's not an issue? I feel relieved now! thank you!

 

I know! I thought that maybe it could switch between boost and vacuum, but to no avail!

 

Much below that and the car may idle a bit strange, in the winter it would occasionally drop a little lower as the engine warmed up and I got some nice grunts and pops from the exhaust. Other than that mine's around the same range when coasting or idling. As for the RPD I'm kinda surprised there's no vaccuum indicator since the farther you are in vaccuum, the better your fuel economy...I thought GM would have accounted for this and included it on the digital display...ah ha, my standard little boost gauge DOES have a leg up in one category .

 

And the wierd thing is when u go to change the color of your gauges on the rpd it shows and example boost gauge in kpa (not psi for some reason) but it has both boost and vacuum. Now why do they tease me with this picture if i cant actually set it that way. Damn them

 

On the gauge, it's normal for these cars. On my DashHawk it actually reads 18.60hg to 18.90hg, unless I kick on the AC or something then its around 17.xx, don't remember.

 

such a tease!!

 

That is normal.

 

if you ain't blowing, you're sucking