Mazda Rotary Club

General => General Technical => Anything Engine/Performance/Tuning related => Topic started by: Bobbit on September 25, 2007, 11:31:48 PM

Title: More turbo woes!
Post by: Bobbit on September 25, 2007, 11:31:48 PM
Hi, got a bit of a problem with me lil car. The charge relief valve seems to be venting boost all the time. Now as i understand it, the valve should vent boost from 3000 untill 4500 rpm and then stop so the boost goes to the engine and not out the valve. Does anyone know what could cause this??

I\'ve tried a 2nd valve and it still does it. I\'m currently running 13/14psi with a pressure regulator (set to 10psi) to reduce the pressure on the control systems. I\'ve also just replaced all the pills and did the rats nest about a year ago.

Thanks for any help.
Title: More turbo woes!
Post by: ianelvar on September 26, 2007, 05:30:35 PM
Is the charge control valve working properly? If it\'s not opening up then the charge from the second turbo will have to go through the charge relief valve as it won\'t be able to get through the butterfly in the Y pipe.
What boost pattern do you get?
Title: More turbo woes!
Post by: Bobbit on September 26, 2007, 11:34:14 PM
boost reads 14psi from 2500ish to 4000, then drops to 10psi, then at 4500 the boost gradually drops off. I can hear the charge relief valve venting, sometimes it is a constant psst, and others it\'s like psst, pause, pssh, pause etc.
The problem is not always constant, however it does occur alot more frequently than not.
I\'ll check the charge control valve/actuator.
Thanks for the advice bud.
Title: More turbo woes!
Post by: Bobbit on October 13, 2007, 06:18:28 PM
How do i check if the charge control valve is working correctly? Doh
Title: More turbo woes!
Post by: ianelvar on October 15, 2007, 01:06:30 PM
Lol. I struggled with that one too. It\'s on page F-87 of the FSM, and a slightly different method on the good old: http://www.autosportracetech.com/RX-7/TurboTroubleshooting.htm

Or to cut a long story short, make sure it moves and stays when some vacuum is applied. Check the control solenoids as well, could just as easily be a problem there.