VAC/Boost numbers

[MicaSp33d]

lately my VAC at idle is around 17s ... after a few minutes of driving it then reaches 20s ... and sometimes goes back to 17s

do i have a vaccum leak and possible boost leak?

 

[opt_ms3]

I noticed when I'm idling with the AC on or turn the wheel it jumps to -17, so its probably normal

 

[Speed3Rookie]

I think he has a leak.
20-21 hg of vacuum is normal for idleing.
About 19 when the compressor kick ins.

 

[phillyb]

i disagree, i think you're fine. i see -17 up to -22 sometimes and i think it has more to do with cold starts, temperature otherwise, and other s***..idk really, but i don't have any leaks

 

[skeeter149]

i disagree, i think you're fine. i see -17 up to -22 sometimes and i think it has more to do with cold starts, temperature otherwise, and other s***..idk really, but i don't have any leaks

i second philly i see about 19-20~ at idle and like 17 with ac on. i think your fine as well(guitar)

 

[bykeryder4life]

assuming your a/c is off.....when you first start the car it will be something like -17 and once the engine runs for a second or warms up it should be sitting around -20 to -21 given your at sea level no elevation taken into account. so if your vac is -17 sometimes while the engine is completely warm you have some kind of leak

 

[mckraut]

i second philly i see about 19-20~ at idle and like 17 with ac on. i think your fine as well(guitar)

I agree with both of them. If I'm at idle with the A/C on, I'll get around -17. If it's off, then anywhere between -20 and -22.

 

[Speed3Rookie]

Lately my VAC at idle is around 17s ... after a few minutes of driving it then reaches 20s ... and sometimes goes back to 17s

do i have a vaccum leak and possible boost leak?

I repeat..this is not normal. Anyone notice he stated "lately".

 

[AFcadet]

It all depends on when you look at your boost gauge. When I first turn on my car when it has been sitting for a long time the car idles at 2,000 rpm...then slowly starts to drop. When it idles high after sitting for a long time my boost gauge will show around -17 vac. But after it starts to warm up and the RPM idle drops to the normal ~800 RPM then it reads 20-21 vac.

If you car is warm...and sitting still idling..it should not be at 17. I'll see 19-18ish vac when I'm idling with the A/C going.

 

[MicaSp33d]

well numbers look normal now ... i get 18-19s on cold start (well its not cold hear in cali) and 20 when warm. even 18-19s and sometimes 20 with the a/c on now.

it could have been the weather affecting the tubes. I will just keep looking at the boost gauge just to make sure .. but all seems fine right now. But im not gonna rule out the possibility of boost leak.