Vacuum is only Reading 12?
 

wasup yall my Vaccum is only reading 12khg whatever u call it.. so any ideas??
oh and Idle everything is Perfectly fine.. drivers fine nothing wrong..
check my Sign for my mods
so ....... i dunno..

my boost does fluctuate when i get on the gas.. so instead of 10 .. keeps going back and forth 8-10.... i dunno.. i searched about that and only thing i could think of was the actuator .. but dunno what to do..

and I have a AutoMeter boost gauge/Vaccum.

1st. - wasup with the VAccum

2nd. - y is my boost pulsing.

Sounds like a boost leak.

????? boost leak @ full boost.. i mean throttle?... could that be??? BOV maybe??

Could be a Vac leak, could be a tired engine, could be a bad gauge. First verify the gauge reading with a known good gauge. Then Check compression. Of other gauge reads 12inhg, and the compression is above 90psi on all faces..
Looks like you have you self a vac leak.. good luck on finding it.

If you're using that crappy nylon hose/brass ferrule setup that Autometer includes, it will leak if you disassemble and reassemble it more than once. Get a brass fitting that screws into the back of the gauge that has a hose barb, and run a proper vacuum line to the gauge to start with. Or get a better gauge...:)

Second, if you have the air pump on your car, make sure it's working. It's common for the insulation on the wiring going to the air pump to flake off, and the wires short to ground and blow the air pump fuse. It's the same as the AC fuse under the hood. With the air pump not running, vacuum will drop and idle and throttle response will be rough.

Check the easy things first :).

Dale

what should the vacuum read at idle? in neutral

on a healthy stock port motor, 17-19hg

how about a factory motor with down pipe mid pine catback, pfc, mine only at 15 when its in park(yes its a auto) but it seems to run strong. im gonna check the ac fuse under the hood. is it beside the battery?

never mind my vaccum is fine its reading 16-18... my mistako

my Boost still fluctuating... pulsing whatever the hell..

sounds like boost/vacuum leak.

my turbos are the poor man's nonsequential, I got the flapper door wired open. when it came off and the door was half open I got pulsating, not steady boost.

would vac read less on a ported motor?

just for info, vaccum reading will vary depending in altitude and weather. Vaccum reding is not a accurate way to see if you have a healthy motor.

It will also vary with even small idle speed changes and operating temp of engine.

Yes

Dave

Streetported motor vacuum runs around 14-15 in.

tom

I see anywhere from 10 to 14 inches mercury on my heavily ported motor, depending on rpm.

Very low vacuum is an indication of a hurt motor, especially of the vacuum has a rhythmic fluctuation to it. Seeing 8 inches of vacuum at idle on a stock/streetported motor is never a good thing.