Low Vacuum

Heads, valves, pistons, rods, crankshaft, etc...

Moderators: Helpinators, Moderators

Post Reply
The big weave
In Neutral
Posts: 16
Joined: Fri Aug 14, 2009 8:57 am

Low Vacuum

Post by The big weave »

Some days my car will pull 15 pounds at idle and 10-11 with the AC on. then today it started to pull 13 but still pulled 10-11 with the ac.

Both reading are for vacuum at idle. no vacuum leaks and has a saab intercooler.
92ss 5-speed winestone

92 Galant VR4 554/1000

And yes its rally ready
Top
ericem
Fifth Gear
Posts: 3242
Joined: Mon Oct 16, 2006 9:44 pm
Location: Toronto,ON Canada

Post by ericem »

When you put a load on the engine there will be less vacuum so unless something is dragging like the A/C clutch or the clutch clutch. Or your timing could be off.
1993 Subaru Legacy L AWD Wagon R.I.P
1994 Subaru Legacy SS R.I.P :(
2004 Nissan Titan LE 4X4
2007 Subaru Legacy GT :)
Top
The big weave
In Neutral
Posts: 16
Joined: Fri Aug 14, 2009 8:57 am

Post by The big weave »

Cam timing or ignition timing?
92ss 5-speed winestone

92 Galant VR4 554/1000

And yes its rally ready
Top
BSOD2600
Fourth Gear
Posts: 1636
Joined: Tue Sep 12, 2006 6:49 am
Location: Seattle, WA

Post by BSOD2600 »

15 inHg at idle? That's out of spec, should be a solid 19-20 inHg.

'11 WRX Limited
'94 SS | 3" TBE, 07 TMIC, TD05H-16G, Revtronix Stage 2, Walbro -- Sold
'94 TW | R.I.P.
Top
gijonas
Fourth Gear
Posts: 1010
Joined: Sat Nov 08, 2008 10:57 pm
Location: Damariscotta, Maine

Post by gijonas »

Yeah i think i get like 22.
94SS.Wiseco forged pistons,TD04,TMIC,WALBRO 225,440's,3" all the way,revtronix stage 2,enough other crap to fill the internet.

THE TRIBUTE BUILD>>>LINKY LINK>>> http://bbs.legacycentral.org/viewtopic.php?p=295455#295455
Top
RJ93SS
Third Gear
Posts: 853
Joined: Mon Jan 14, 2008 7:55 am
Location: Vancouver, Canada

Post by RJ93SS »

first we need to know where your from.

second we need to know what type of gauge your using and is it reliable.

and last, how positive are you that you have no leaks?

Thanks
93SS 04 wrx brakes/slotted w/ hawks--TD05 -- 06 I/C -- 20mm n/a fsb -- Stage 2 -- 550's -- Perrin DIV DP -- 2-3/4 Tit Exhaust -- K&N -- C/C -- A/C Delete -- Grounded -- GT Leather Interior -- WRX/STI Strut Setup -- 17" 225's -- 2 Kids Seats ;)
Top
ericem
Fifth Gear
Posts: 3242
Joined: Mon Oct 16, 2006 9:44 pm
Location: Toronto,ON Canada

Post by ericem »

My car is only 18-19 hg via select monitor.
1993 Subaru Legacy L AWD Wagon R.I.P
1994 Subaru Legacy SS R.I.P :(
2004 Nissan Titan LE 4X4
2007 Subaru Legacy GT :)
Top
RJ93SS
Third Gear
Posts: 853
Joined: Mon Jan 14, 2008 7:55 am
Location: Vancouver, Canada

Post by RJ93SS »

also, is the engine warm at this reading.
i see 16-17 on start up and 18-19 when warm.

his gauge could easily be off.

are u seeing steady boost, and what is it on what set up?
93SS 04 wrx brakes/slotted w/ hawks--TD05 -- 06 I/C -- 20mm n/a fsb -- Stage 2 -- 550's -- Perrin DIV DP -- 2-3/4 Tit Exhaust -- K&N -- C/C -- A/C Delete -- Grounded -- GT Leather Interior -- WRX/STI Strut Setup -- 17" 225's -- 2 Kids Seats ;)
Top
The big weave
In Neutral
Posts: 16
Joined: Fri Aug 14, 2009 8:57 am

Post by The big weave »

I think the boost gauge might be off, when you turn the car off it sits are 1 pound of boost. its an autometer phantom. I have not checked for leaks I dont hear any and the car idles at 700 perfectly.
92ss 5-speed winestone

92 Galant VR4 554/1000

And yes its rally ready
Top
SLODRIVE
Third Gear
Posts: 662
Joined: Fri Nov 21, 2008 1:27 am
Location: Colorado, north of Highway 52
Contact:
Contact SLODRIVE

Post by SLODRIVE »

The altitude where you live can also be a factor. Here at 5000 feet, I'm seeing around 16 inches of vacuum at cold idle, and about 18 when warmed up. I'm sure both readings would be at least 2-3 inches higher at sea level.
http://www.slodriveracing.com
-92 SS 5MT- EJ20H swap, Haltech standalone ECU, TD04, FXT TMIC, 3" exhaust, STi/AGX struts, JDM 5-speed, 4.111 LSD rear, Blitz EBC, etc.
-'93 L Wagon - Pink Roll Cage - "Dirty Leg"
-And more!
Top
Post Reply

Return to “Engine”