Welcome to the North American Subaru Impreza Owners Club Thursday July 10, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Normally Aspirated Powertrain

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 04-12-2005, 02:18 PM   #1
tompetey
Scooby Newbie
 
Member#: 73034
Join Date: Oct 2004
Location: Rochester, NY
Vehicle:
MY02 OBS

Default Vacuum Test

Did a search and came up with a bunch of info but not a step-by-step approach. Just need to know how to perform a vacuum test (options, tools, procedure...). Anything that may help as I would like to get this done today or tomorrow. Thanks
* Registered users of the site do not see these ads.
tompetey is offline   Reply With Quote
Old 04-12-2005, 02:56 PM   #2
Ramon_12345
Scooby Newbie
 
Member#: 72021
Join Date: Oct 2004
Location: BARBADOS
Vehicle:
1999 JDM GC1 IMPREZA
WHITE

Default

5. Intake Manifold Vacuum
A: MEASUREMENT
1) Warm-up the engine.
2) Disconnect the brake vacuum hose and install
the vacuum gauge to the hose fitting on the manifold.

3) Keep the engine at the idle speed and read the
vacuum gauge indication.
By observing the gauge needle movement, the
internal condition of the engine can be diagnosed
as described below.

Vacuum pressure (at idling, A/C “OFF”):
Less than −60.0 kPa (−450 mmHg, −17.72
inHg)

Diagnosis of engine condition by measurement of manifold vacuum
Vacuum gauge indication Possible engine condition

1. Needle is steady but lower than normal position. This tendency
becomes more evident as engine temperature rises.
Leakage around intake manifold gasket or disconnection or
damaged vacuum hose

2. When engine speed is reduced slowly from higher speed,
needle stops temporarily when it is lowering or becomes
steady above normal position.
Back pressure too high, or exhaust system clogged

3. Needle intermittently drops to position lower than normal
position.
Leakage around cylinder

4. Needle drops suddenly and intermittently from normal position.
Sticky valves

5. When engine speed is gradually increased, needle begins
to vibrate rapidly at certain speed, and then vibration
increases as engine speed increases.
Weak or broken valve springs

6. Needle vibrates above and below normal position in narrow
range.
Defective ignition system or throttle chamber idle adjustment
Ramon_12345 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Car will not enter test mode. jmikolich Newbies & FAQs 19 07-09-2010 01:59 AM
So how was your last test drive? dome24 Alaskan Impreza Club Forum -- AKIC 8 06-04-2010 06:47 PM
Vacuum leak test ElSpa Factory 2.0L Turbo Powertrain 1 06-07-2009 12:30 PM
Brass Vacuum Hose Insert and T Vacuum Hose adapter blitzej20 Engine/Power/Exhaust 8 08-28-2006 08:35 PM
Boost vacuum leak test procedure help Ricowrx Factory 2.5L Turbo Powertrain 0 05-30-2005 12:17 PM


All times are GMT -4. The time now is 08:12 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.