Automotive Forums .com - the leading automotive community online! Automotive Forums .com - the leading automotive community online!
Automotive Forums .com - the leading automotive community online! 
-
Latest | 0 Rplys
Go Back   Automotive Forums .com Car Chat > Mitsubishi > Eclipse/Talon/Laser > Engine, Transmission and Drivetrain
Engine, Transmission and Drivetrain Discuss Engine, Transmission, Drivetrain, and all other performance modifications here.
Reply Show Printable Version Show Printable Version | Email this Page Email this Page | Subscription Subscribe to this Thread
 
Thread Tools
Old 11-16-2011, 12:48 AM   #16
gallacmic
AF Newbie
Thread starter
 
gallacmic's Avatar
 
Join Date: May 2009
Location: Riverton, Utah
Posts: 30
Thanks: 1
Thanked 0 Times in 0 Posts
Re: The big 420a Mystery! Please Help!!!

Alright so I thought I would post an update about the BOV issues I have been having as I just made a discovery today. I decided to buy one of those Harbor freight brake bleeder vacuum pump kits that has a gauge on the vacuum gun. I first connected the gun to the hose that feeds the BOV its boost and vacuum pressure and started up the engine. The gauge read 15hg at idle. I also know that the exact opposite of 1hg is .5 psi. So you want a spring that has half the pressure rating of whatever the hg is on the vacuum gauge. So in my case 15hg means I need a 7.5 psi spring in the BOV. So next I disconnected the gun and hooked it to the BOV to do a vacuum test on it to see when the spring would open up. NO VACUUM AT ALL!!! The BOV will not even hold 1hg of vacuum!! GO FIGURE IT PASSES THE BOOST LEAK TEST!!! So that was the mystery! I need to seal it for both boost and vacuum in order for the engine to do its job to open the damn thing. I never would have guessed that the BOV is not getting any vacuum above the diaphragm. But anyways now I know what I need to do I hope this helped point someone in the right direction if they were having similar issues. Also thanks again to all the nice people who responded to this post to help me out!
gallacmic is offline   Reply With Quote
Old 11-17-2011, 10:35 AM   #17
SilvrEclipse
Holset powered 420a
 
SilvrEclipse's Avatar
 
Join Date: May 2005
Location: Florence, South Carolina
Posts: 4,434
Thanks: 1
Thanked 14 Times in 12 Posts
Send a message via AIM to SilvrEclipse
Re: The big 420a Mystery! Please Help!!!

My bov also will not hold vaccum in a test like that, it has a slow leak but this doesnt effect it since the motor is sucking so much air that it over comes this small leak. You are looking into this too much, with the car idling look at the bov and see if its opening, when you rev the motor the valve should close and open as the motor pulls high vac. If it does not open then you need to lower the spring
__________________
98 Eclipse GS Turbo
Megasquirt 2 - Holset HY35 Turbo - Built motor - P&P Head and Intake - 3" Turbo back - FMIC - Greddy RZ BOV - Walbro 255 - Aeromotive AFPR - 650cc Injectors - Fidanza Flywheel - Zoom clutch - 13" Cobra Front Brakes - AEM WB - Devilsown meth injection - 3.55 Final Drive gear ratio

1981 Chevy Scottsdale
1987 Nissan 300zx - Chump Car
2001 BMW 325i - DD
SilvrEclipse is offline   Reply With Quote
 
Similar Threads
Thread Thread Starter Forum Replies Last Post
95' overheating mystery-please help mollbells Grand AM 1 01-07-2006 10:44 AM
mystery...please help! sjr8ut Corolla/Matrix/Voltz 1 10-12-2004 11:32 AM
mystery...please help! sjr8ut General Discussion 0 10-12-2004 11:12 AM
Big Starting Prob, please Help! blade34609 '88 - '91 Civic | CRX | Wagon | Shuttlee 8 08-04-2003 02:24 AM
BIG technical question! Please help! MR2_Lancer Sentra | 200SX (USDM FWD) 2 08-05-2002 06:00 PM

Reply

POST REPLY TO THIS THREAD

Go Back   Automotive Forums .com Car Chat > Mitsubishi > Eclipse/Talon/Laser > Engine, Transmission and Drivetrain

Thread Tools

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



All times are GMT -5. The time now is 11:19 AM.

Community Participation Guidelines | How to use your User Control Panel

Powered by: vBulletin | Copyright Jelsoft Enterprises Ltd.
 
 
no new posts