CTR_B

iTrader: (1)

For somereason when my car gets warned up it has around 25hng of vacum, This scares me for two resaons

1. it was always between 15-20

2 my gauge only goes to 30

What could be the cause of this?, And should I be worried?

gsrhatch2356

get another gauge to make sure that the reading is accurate first. then if it is look for some sort of blockage in the throttle body carbon or hell I have found shop rags in there before so something like this would incresse the vacuum on the gauge but more than likely the gauge is bad.

z6hatchboy

i wouldnt be worried, there supposed to be around that, thats what my turbo z6 had and that was after i rebuilt it. sounds like you mightve had a leak bfore if you had 15

CTR_B

iTrader: (1)

Oh so more is better? Im confused but hey if you can check this out and reply there and its more decript of the problems Im having


https://honda-tech.com/zerothre...88273

TroyboyEK

Well I work on Diesels and I know the more Vacuum the better, because the less vacuum you have means more Pressure and more pressure = More leaks.

Less Vacuum to hold in your fluids.

More pressure the push them out, blow gaskets and o-rings, ect.

That's my $0.2

97Ej6mike

SOunds like your motor is about to blow up.

Actually, 25 sounds about right.
15-20 is a vaccuum leak.

BlackDeuceCoupe

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TroyboyEK &raquo;</TD></TR><TR><TD CLASS="quote">Well I work on Diesels and I know the more Vacuum the better, because the less vacuum you have means more Pressure and more pressure = More leaks.</TD></TR></TABLE>


Huh?

Vacuum in diesels is practically none-existent!

I used to own a diesel, and it would run just fine without the intake manifold installed.

All the manifold did was give you a place to hang the air cleaner - no butterfly, no nothing - ran WFO all the time!!!

The injector pump controlled the speed, e.g. the amount of fuel it squirted into the cylinders determined the speed - that's all...

How do YOU get vacuum in a diesel?!?!?!?


EDIT


LoL!

Check it out - here's a diesel with no intake OR exhaust manifold!!!

http://www.freerepublic.com/fo...posts




Modified by BlackDeuceCoupe at 5:14 PM 9/6/2008

TroyboyEK

I was talkin Crankcase Vacuum...I work on BIG diesels. Like the one on my Ship ( I'm in the Navy ).

Dont know what kinda diesel your speaking off. But hey I'm always willing to learn something new if you wanna enlighten me

BlackDeuceCoupe

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TroyboyEK &raquo;</TD></TR><TR><TD CLASS="quote">I was talkin Crankcase Vacuum...I work on BIG diesels. Like the one on my Ship ( I'm in the Navy ).</TD></TR></TABLE>


They still run diesel engines in navy ships?!?!?!?

My crankcase had positive pressure - unbelieveable blow-by at 22:1 compression WFO - turned the oil black immediately after an oil change!

CTR_B

iTrader: (1)

Uh guys?

BlackDeuceCoupe

Um...

Are we getting carried away?

thesmogman

I was taught that 18 to 22 in.hg. is normal. However when you decelerate you will notice it going into the 30's or more depending on how hard you decel.

I would be more worried at 15.

TroyboyEK

Sorry CTR.

But ya more = Better.

CTR_B

iTrader: (1)

Thanks

gsrhatch2356

before this goes any furthur I think all should really study up on characterics of engine dynamics. first of all I live in texas and it is nearlly impossible to get 25inhg of vacuum you would have to have a motor that has nearly 100% efficiecny. you have to take into consideration that altitude has alot to do with it considering the wieght of the air. I dont know what and the hell pressure has to do with anything cause unless you run a turbo this does not exist on a NA motor. thesmogman is correct in saying that 18-22inhg is normal I personely get 23inhg being that I live at such a low altitude. yes when you are coming out of a shift or slowing down vacuum does go up by a few inhg but never will it hit 30inhg I dont care where you live. yes 15inhg is low and there are other things that can cause this besides what I mentioned earlier but since you didnt mention any drivabillity problems, they seemed to be the most relavent. seriously go to a shop where a tech has a $150.00 snap on vac gauge and compare it to your own, I think you will be surpised in what you find. also if you are experincing problems check the timing. GL. and no hard feeling to anybody else but it was starting to stray a little to far for me. crankcase pressure and diesels have nothing to do with this problem.

CTR_B

iTrader: (1)

There are really no drivability issue as far as the vac goes. I notice that it gets More and More vac when Im off the gas completely and just ideling down or if Im in 5th and cruising at 35-40 that is the only time I see that gauge that far down.