low vaccumm???

[blowinsmoke95]

whats your guys vaccumm gauges say when the car is at an idle? mine currently sits at 11 STEADY... unsure if this is normal or not... also, anything past 3/4 throttle it sputters... overall the whole time its running, you can smell raw fuel... i dont have my wideband bunged into my new downpipe yet so im completely unsure of what exactly my afr's are... any suggestions are welcome!!!

 

[RadDsm]

What cams do you have?

That will make a difference in your vacuum reading.

 

[1twistdtalon]

Boost leak test. A boost leak will cause your car to run rich, Run badly and effect you vacuum.

 

[blowinsmoke95]

factory first gen cams, that i know of... the motor thats in my car is a bit of a freak... much like the person who owned it before me... so its hard to tell exact specs of this motor... i just did a minor overhaul of this motor, and the ONLY gasket that wasnt changed was the intake mani... how hard is it to pull just the manifold off (without pulling the head) if this is to be the suspected leak??1

 

[1twistdtalon]

I just pulled mine and changed the gasket,

I found that pulling the battery And battery box, then the intercooler and TB is the best way to get it out. Then if you still have the bracket on the back of the motor that goes from the intake to the block its best to just pull the bottom bolt, And take it out with the intake then take it off at throw it in the metal pile.

You will also need to take all wires and cables off, Along with anything on the fire wall that is in the way.

Good luck.

 

[blowinsmoke95]

OKAY... i also have read that if the boost control silenoids arent hooked up you will have low vaccumm readings??? i dont understand this concept, but seeing as my car doesnt idle rough/high/or anything out of the normal, i cannot forsee it being a leak....

 

[GsxEcutioner]

same problem here except its idle vacuum is like 12-14 in HG, so please let me know if you figure your problem out, i think i need to retime the car.
-shane

 

[350war]

Im running 18-19 hg @ idle pretty much stock engine with emissions delete.

 

[stariondriver75]

Did you have the intake manifold off then reuse the gasket? Torqued everything correctly? I'd be suspect of the gasket if so

 

[viprez586]

Boost leak test. A boost leak will cause your car to run rich, Run badly and effect you vacuum.

This is both of you guys' problem.
Easy way to find vacuum leaks - Start car, let it idle. Spray brake clean on suspected areas that are prone to leaking. If you spray a particular area and the idle raises then you've found your leak.


Normal is 18-20 inhg @ idle.
My original motor with 150k on it, 120psi across all four, bad rings - idled with 15-16inhg.

My current motor pulls 20.

Don't worry about vacuum while your driving or cruising - it's all over the place depending on throttle position and vehicle load.

 

[blowinsmoke95]

okay guys... found my problem... it was either the intake mani gasket or lower injector seals... i replaced both when i pulled my intake. now, the car at a 900rpm idle, i hold a constant 20-22 in-hg. boosts fine and pulls hard again...

 

[viprez586]

Good to hear. Your idle is a little high, it should be at 750. But I like my 1k rpm idle to smooth out my rock solid motor mounts...though it's not a huge improvement. Anyway, helps out with stalling when pushing in the clutch coasting and starting out if your right foot gets a little lazy.